piperidines and Pruritus

Chronic kidney disease-associated pruritus (CKD-aP) has been recognized for over a century. The complex pathophysiology of CKD-aP makes it challenging to find an effective treatment; the proposed therapeutic options come from anecdotal reports and small clinical trials, which at best compare the test drug against placebo. Gabapentinoids have shown relevant efficacy but there are serious safety concerns about their possible central nervous system toxicity. Recently difelikefalin, a κ-opioid receptor agonist, has been the first Food and Drug Administration (FDA)-approved drug for moderate-severe CKD-aP treatment. Approval from other regulatory agencies is expected in 2022. In this article, preclinical, pharmacokinetic and safety studies on difelikefalin are reported, but a great part of the data derive from meeting abstracts and non-peer-review communications and this is a possible cause for concern regarding bias in publication. A review of published and unpublished studies about difelikefalin in CKD-aP treatment is provided. Currently, two published large trials show that difelikefalin offers a new therapeutic opportunity to treat CKD-aP, a condition that leads to both worse survival and quality of life in hemodialysis patients.

Topics: Humans; Piperidines; Pruritus; Quality of Life; Renal Dialysis; Renal Insufficiency, Chronic; United States

Difelikefalin (Korsuva

Topics: Adult; Drug Approval; Drug Development; Humans; Piperidines; Pruritus; Receptors, Opioid, kappa; Renal Dialysis; Renal Insufficiency, Chronic

Topics: Europe; Humans; Kidney Failure, Chronic; Piperidines; Pruritus; Renal Dialysis

Topics: Adolescent; Adult; Benzimidazoles; Child; Drug Interactions; Histamine H1 Antagonists; Humans; Piperidines; Pruritus; Quality of Life; Rhinitis, Allergic; Urticaria; Young Adult

This article provides a focused update on uremic pruritus, highlighting the latest evidence concerning the epidemiology, pathophysiology, and treatment options for this common and bothersome condition.. Half of dialysis patients and a quarter of those with nondialysis chronic kidney disease experience bothersome itch that reduces quality of life and is increasingly recognized to be associated with poor outcomes including mortality. The KALM-1 trial, which reported effective symptomatic relief with difelikefalin, has bolstered support for the role of an imbalance of μ and κ-opioid receptor activity in pruritogenesis. The role of a chronic inflammatory state, increased cytokine levels and altered immune signaling in pruritogenic nerve activation continues to be elucidated with basic science, which paves the wave for future novel therapeutics. In the meantime, gabapentin appears to be the most evidence-based widely available uremic pruritus treatment, as long as care is taken with dosing and monitoring of side-effects.. Uremic pruritus remains a top research priority. Patients with uremic pruritus may be able to look forward to a new decade of understanding, knowledge, and novel treatment options for this burdensome condition. As difelikefalin and other potential agents come to market, cost-effectiveness assessments of these interventions will help determine if the widespread use of them is feasible amongst renal programs.

Topics: Gabapentin; Humans; Piperidines; Pruritus; Renal Dialysis; Renal Insufficiency, Chronic

To address the current trends of therapeutic mechanisms for treatment of allergic conjunctivitis (AC), based on topical antihistamines and mast cell stabilizers (MCS).. The antihistamine drug alcaftadine has H4 receptor inverse agonism, anti-inflammatory and MCS activities. The antihistamines levocabastine and azelastine are more effective than placebo in treatment of AC symptoms in randomized controlled trials (RCTs). The topical dual-action antihistamines/MCS olopatadine, azelastine, ketotifen, and epinastine are commonly used in Europe and in the United States for mild subtypes of AC. For the main symptoms of AC, ocular itch and conjunctival hyperemia, epinastine 0.05% was superior to placebo, but equal or more effective than olopatadine 0.1%, while the later was more effective than ketotifen. High concentration olopatadine 0.77% had longer duration of action, better efficacy on ocular itch, and a similar safety profile to low-concentration olopatadine 0.2%. The new formulas of topical dual-action agents present longer duration of action, leading to a decreased frequency of use.. The topical dual-action agents are the most effective agents treating signs and symptoms of mild forms of AC. There is superiority to the high-concentration olopatadine drug over other agents on ocular itch, with prolonged effect when used once-daily.

Topics: Administration, Ophthalmic; Anti-Allergic Agents; Benzazepines; Conjunctivitis, Allergic; Cromolyn Sodium; Dibenzazepines; Histamine Antagonists; Humans; Hyperemia; Imidazoles; Ketotifen; Nedocromil; Olopatadine Hydrochloride; Phthalazines; Piperidines; Pruritus; Pyridines; Pyrimidinones

Bepotastine besilate 1.5% is a newly approved second-generation topical antihistamine indicated for the pruritus associated with allergic conjunctivitis. In Japan, the oral formulation is approved to manage pruritus associated with allergic rhinitis and urticaria.. Bepotastine is a piperidine derivative that antagonizes H1 receptors with high selectivity. It has been labeled a dual-acting or multiple-acting antiallergic medication, because it inhibits histamine at H1 receptors and stabilizes mast cells to prevent histamine release. Bepotastine may also have other immunoactive properties, such as inhibition of eosinophil migration, interleukin-5 (IL-5), leukotrienes (e.g., LTB4) and platelet-activating factor (PAF). Human clinical trials demonstrate the efficacy and safety of systemic and ophthalmic bepotastine for pruritus relief, limited penetration across the blood-brain-barrier and kinetics suitable for twice-daily administration.. Bepotastine besilate 1.5% ophthalmic solution is a safe and effective treatment option for allergic conjunctivitis associated pruritus. Side-effect profile is similar to other ocular antihistamine agents. Additional comparative-effectiveness studies would further advance its clinical use. Oral bepotastine is a safe and effective treatment option approved in Japan for allergic rhinitis, urticaria and pruritus associated with skin diseases.

Topics: Administration, Cutaneous; Administration, Oral; Animals; Clinical Trials as Topic; Conjunctivitis, Allergic; Histamine H1 Antagonists; Humans; Piperidines; Pruritus; Pyridines; Rhinitis, Allergic; Rhinitis, Allergic, Perennial; Urticaria

Oral bepotastine is a second-generation histamine H(1) receptor antagonist that also suppresses some allergic inflammatory processes. Numerous short- and long-term clinical trials and surveillance studies have shown that twice-daily bepotastine is an effective and generally well tolerated antihistamine in the treatment of patients with allergic rhinitis, chronic urticaria or pruritus associated with skin conditions (eczema/dermatitis, prurigo or pruritus cutaneus). Bepotastine 20 mg/day was significantly more effective than terfenadine 120 mg/day in patients with perennial allergic rhinitis, as evaluated by the final global improvement rating and several other endpoints in a phase III trial. In phase III trials in patients with chronic urticaria, bepotastine 20 mg/day was more effective than placebo in improving levels of itching and eruption, and as effective as terfenadine 120 mg/day with regard to the final global improvement rating and other endpoints. In a noncomparative trial in patients with pruritus associated with skin diseases, the majority of bepotastine recipients in the overall population, as well as in the specific skin disease subgroups (eczema/dermatitis, prurigo or pruritus cutaneus), had a final global improvement rating of moderate or greater. Bepotastine was generally well tolerated in adult and paediatric patients with allergic conditions.

Topics: Administration, Oral; Anti-Allergic Agents; Histamine H1 Antagonists; Humans; Hypersensitivity; Piperidines; Pruritus; Pyridines; Rhinitis, Allergic, Perennial; Urticaria

The purpose of this review is to examine published non-clinical literature on the antihistamine bepotastine besilate, including pharmacokinetic and pharmacologic properties.. Standard literature searches using diverse databases were used to find articles on bepotastine besilate published between 1997 and 2009. Articles primarily described non-clinical data utilized for the development of an oral formulation of bepotastine besilate and were published in Japanese. No publications of non-clinical data for an ophthalmic formulation were found in the database searches.. Bepotastine besilate is a second-generation antihistamine drug possessing selective histamine H(1) receptor antagonist activity. Bepotastine has negligible affinity for receptors associated with undesirable adverse effects, including histamine H(3), α(1)-, α(2)-, and β-adrenergic, serotonin (5-HT(2)), muscarinic, and benzodiazepine receptors. Bepotastine possesses additional anti-allergic activity including stabilization of mast cell function, inhibition of eosinophilic infiltration, inhibition of IL-5 production, and inhibition of LTB(4) and LTD(4) activity. Bepotastine in vivo dose-dependently inhibited the acceleration of histamine-induced vascular permeability and inhibited homologous passive cutaneous anaphylaxis in guinea pig studies. In mouse models of itching, oral bepotastine inhibited the frequency and duration of scratching behavior. Multiple in vivo animal toxicology studies have demonstrated bepotastine to be safe with no significant effects on respiratory, circulatory, central nervous, digestive, or urinary systems. The concentration of bepotastine after intravenous administration of bepotastine besilate (3 mg/kg) in rats was lower in the brain than in plasma, predicting reduced sedation effects compared to older antihistamines.. Non-clinical in vitro and in vivo studies have demonstrated bepotastine is a histamine H(1) receptor antagonist with favorable pharmacokinetic, pharmacologic, safety, and antihistamine properties as well as operating on other pathways leading to allergic inflammation beyond those directly involving the histamine H(1) receptor.

Topics: Animals; Anti-Allergic Agents; Conjunctivitis, Allergic; Disease Models, Animal; Drug Evaluation, Preclinical; Histamine Antagonists; Humans; Mice; Piperidines; Pruritus; Pyridines; Rats

Bilastine is a nonsedating second-generation antihistamine for the symptomatic treatment of allergic rhinoconjunctivitis and urticaria. Our study aimed to evaluate the optimal dose, efficacy, and safety of a newly developed once-daily preservative-free ophthalmic formulation of bilastine for allergic conjunctivitis.. Our phase 2, single-center, double-masked, randomized trial compared the efficacy of 3 doses of a bilastine ophthalmic formulation (0.2%, 0.4%, and 0.6%) with that of vehicle for the treatment of allergic conjunctivitis. The primary efficacy endpoint was the reduction in ocular itching. The Ora-CAC Conjunctival Allergen Challenge model was used to assess ocular and nasal symptoms at the onset of action (15 minutes) and at 8- and 16-hours after treatment. Tolerance and safety were also evaluated.. A total of 121 adults with seasonal and/or perennial ocular allergy were randomized. Bilastine ophthalmic formulations 0.2%, 0.4%, and 0.6% were significantly superior (P>.001) to vehicle for the treatment of ocular itching at 3, 5, and 7 minutes after challenge at onset of action (15 minutes) and at 8 hours after treatment. Bilastine 0.6% was also effective at 16 hours after treatment. Treatment differences for bilastine 0.6% were statistically significant (P<.001) compared to vehicle at all timepoints for tearing, eyelid swelling, and nasal symptoms. No relevant adverse events were observed.. All the tested ophthalmic bilastine doses were efficacious for rapid reduction of ocular itching. The 0.6% formulation was effective up to 16 hours after treatment, making it suitable for once-daily administration. The new formulation was safe and well tolerated.

Topics: Adult; Anti-Allergic Agents; Benzimidazoles; Conjunctivitis, Allergic; Double-Blind Method; Humans; Ophthalmic Solutions; Piperidines; Pruritus

Notalgia paresthetica is a neuropathic disorder characterized by pruritus in a circumscribed region of the upper back. Difelikefalin, a selective kappa opioid receptor agonist, has shown efficacy in other chronic pruritic conditions and is being investigated for the treatment of notalgia paresthetica.. In this phase 2, double-blind, placebo-controlled trial, we randomly assigned, in a 1:1 ratio, patients with moderate-to-severe pruritus caused by notalgia paresthetica to receive 2 mg of oral difelikefalin or placebo twice daily for 8 weeks. The primary outcome was the change from baseline at week 8 in the weekly mean score on the daily Worst Itch Numeric Rating Scale (WI-NRS; scores range from 0 [no itch] to 10 [worst itch imaginable]). The secondary clinical outcomes were itch-related quality-of-life and itch-related sleep measures.. A total of 126 patients were enrolled; 62 patients were assigned to receive difelikefalin, and 63 were assigned to receive placebo. One patient who had been assigned to receive difelikefalin withdrew consent before the first dose and is not included in the main analyses. The mean baseline WI-NRS score was 7.6 (indicating severe itch) in each group. The change from baseline in the weekly mean WI-NRS score at week 8 was -4.0 points in the difelikefalin group and -2.4 points in the placebo group (difference in change, -1.6 points; 95% confidence interval, -2.6 to -0.6; P = 0.001). The results for the secondary outcomes generally did not support those of the primary analysis. Headache, dizziness, constipation, and increased urine output occurred more frequently in the difelikefalin group than in the placebo group.. Among patients with notalgia paresthetica, oral treatment with difelikefalin resulted in modestly greater reductions in itch intensity scores than placebo over a period of 8 weeks but was associated with adverse events. Larger and longer trials are needed to assess the efficacy and safety of difelikefalin treatment in this disorder. (Funded by Cara Therapeutics; KOMFORT ClinicalTrials.gov number, NCT04706975.).

Topics: Back; Double-Blind Method; Humans; Peripheral Nervous System Diseases; Piperidines; Pruritus; Receptors, Opioid, kappa; Treatment Outcome

Chronic pruritus is burdensome for patients with chronic kidney disease (CKD).. We evaluated difelikefalin efficacy and safety in reducing itch in subjects with non-dialysis-dependent CKD and those undergoing hemodialysis (HD).. This phase 2, double-blind, randomized, placebo-controlled, dose-finding study enrolled non-dialysis-dependent CKD (stage 3-5) and HD subjects with moderate-to-severe pruritus. Subjects were equally randomized to oral difelikefalin (0.25, 0.5, or 1.0 mg) or placebo once daily for 12 weeks. The primary end point was the change in the weekly mean Worst Itching Intensity Numeric Rating Scale (WI-NRS) score at week 12.. Two hundred sixty-nine subjects were randomized (mean [SD] baseline WI-NRS: 7.1 [1.2]). Difelikefalin 1.0 mg significantly reduced weekly mean WI-NRS scores versus placebo at week 12 (P = .018), with numerical reductions observed with difelikefalin 0.25 and 0.5 mg. At week 12, 38.6% of subjects receiving difelikefalin 1.0 mg achieved a complete response (WI-NRS 0-1) versus 14.4% receiving placebo. Difelikefalin resulted in ∼20% improvement in itch-related quality-of-life measures. The most common treatment-emergent adverse events were dizziness, fall, constipation, diarrhea, gastroesophageal reflux disease, fatigue, hyperkalemia, hypertension, and urinary tract infection.. Study duration was 12 weeks.. Oral difelikefalin significantly reduced itch intensity in stage 3-5 CKD subjects with moderate-to-severe pruritus, supporting continued development for this condition.

Topics: Double-Blind Method; Humans; Kidney Failure, Chronic; Piperidines; Pruritus; Renal Dialysis; Severity of Illness Index

Patients with pruritus receiving hemodialysis frequently experience oppressive physical and psychiatric symptoms that directly affect their quality of life and increase mortality. However, treatment options are limited.. To determine the clinically recommended dose of difelikefalin, a κ-opioid receptor agonist, based on the efficacy, dose response, safety, and pharmacokinetics.. This randomized, double-blind, placebo-controlled, 4-arm phase 2 trial was conducted from February 1, 2019, to October 22, 2019, at 94 sites in Japan. Patients with moderate to severe pruritus receiving hemodialysis were enrolled.. Difelikefalin (0.25, 0.5, and 1.0 μg/kg) and placebo were intravenously administered 3 times a week at the end of each hemodialysis session for 8 weeks.. The primary end point was the change from baseline in the weekly mean Worst Itching Intensity Numerical Rating Scale (NRS) score at week 8. Secondary outcomes measured changes in itch-related quality-of-life score using the Skindex-16 and 5-D itch scale. Safety was assessed according to adverse events, laboratory tests, vital signs, body weight, and 12-lead electrocardiogram.. A total of 247 Japanese patients (186 male [75%]; mean [SD] age, 64.5 [11.7] years) were randomized to placebo (n = 63), 0.25 μg/kg of difelikefalin (n = 61), 0.5 μg/kg of difelikefalin (n = 61), or 1.0 μg/kg of difelikefalin (n = 62). The changes from baseline in the adjusted mean (SE) of the 24-hour Worst Itching Intensity NRS score at week 8 were -2.86 (0.29) in the placebo group, -2.97 (0.29) in the 0.25 μg/kg of difelikefalin group, -3.65 (0.30) in the 0.5 μg/kg of difelikefalin group, and -3.64 (0.30) in the 1.0 μg/kg of difelikefalin group. Significant differences were found in the 0.5 μg/kg of difelikefalin group (adjusted mean difference, -0.80; 95% CI, -1.55 to -0.04; P = .04) and the 1.0 μg/kg of difelikefalin group (adjusted mean difference, -0.78; 95% CI, -1.54 to -0.03; P = .04) compared with placebo. The Skindex-16 overall score and 5-D itch scale total score indicated an improvement with treatment with 0.5 and 1.0 μg/kg of difelikefalin (adjusted weekly mean [SE] Skindex-16 overall score at week 8, -27.79 [2.05]; 95% CI, -31.83 to -23.74 for 0.5 μg/kg of difelikefalin and -22.69 [2.04]; 95% CI, -26.71 to -18.68 for 1.0 μg/kg of difelikefalin; adjusted weekly mean [SE] 5-D itch scale total score at week 8, -6.5 [0.4]; 95% CI, -7.2 to -5.8 for 0.5 μg/kg of difelikefalin and -6.8 [0.3]; 95% CI, -7.5 to -6.2 for 1.0 μg/kg of difelikefalin). The incidence of adverse events was 67% (42 of 63 patients) in the placebo group, 72% (44 of 61 patients) in the 0.25 μg/kg of difelikefalin group, 77% (47 of 61 patients) in the 0.5 μg/kg of difelikefalin group, and 85% (53 of 62 patients) in the 1.0 μg/kg of difelikefalin group. No dependency was reported.. The findings of this phase 2 randomized clinical trial of difelikefalin suggest that 0.5 μg/kg of difelikefalin should be the clinically recommended dose as a new option for treating moderate to severe pruritus in patients undergoing hemodialysis because of its efficacy, acceptable tolerability, and manageable safety profile.. ClinicalTrials.gov Identifier: NCT03802617.

Topics: Female; Humans; Japan; Male; Middle Aged; Piperidines; Pruritus; Quality of Life; Renal Dialysis

Topics: Adult; Aged; Aged, 80 and over; Antipruritics; Double-Blind Method; Female; Humans; Male; Middle Aged; Piperidines; Pruritus; Quality of Life; Renal Dialysis; Renal Insufficiency, Chronic; Treatment Outcome

Topics: Adolescent; Adult; Carbon Dioxide; Cross-Over Studies; Double-Blind Method; Female; Healthy Volunteers; Humans; Incidence; Male; Middle Aged; Oxygen Saturation; Piperidines; Placebos; Pruritus; Receptors, Opioid, kappa; Respiratory Insufficiency; Respiratory Rate; Young Adult

Difelikefalin is a peripherally restricted and selective agonist of kappa opioid receptors that are considered to be important in modulating pruritus in conditions such as chronic kidney disease.. In this double-blind, placebo-controlled, phase 3 trial, we randomly assigned patients undergoing hemodialysis who had moderate-to-severe pruritus to receive either intravenous difelikefalin (at a dose of 0.5 μg per kilogram of body weight) or placebo three times per week for 12 weeks. The primary outcome was the percentage of patients with an improvement (decrease) of at least 3 points from baseline at week 12 in the weekly mean score on the 24-hour Worst Itching Intensity Numerical Rating Scale (WI-NRS; scores range from 0 to 10, with higher scores indicating greater itch intensity). The secondary outcomes included the change from baseline in itch-related quality-of-life measures, the percentage of patients with an improvement of at least 4 points in the WI-NRS score at week 12, and safety.. A total of 378 patients underwent randomization. A total of 82 of 158 patients (51.9%) in the difelikefalin group had a decrease of at least 3 points in the WI-NRS score (primary outcome), as compared with 51 of 165 (30.9%) in the placebo group. The imputed percentage of patients with a decrease of at least 3 points in the WI-NRS score was 49.1% in the difelikefalin group, as compared with 27.9% in the placebo group (P<0.001). Difelikefalin also resulted in a significant improvement from baseline to week 12 in itch-related quality of life as measured by the 5-D itch scale and the Skindex-10 scale. The imputed percentage of patients with a decrease of at least 4 points in the WI-NRS score at week 12 was significantly greater in the difelikefalin group than in the placebo group (37.1% [observed data: 64 of 158 patients] vs. 17.9% [observed data: 35 of 165 patients], P<0.001). Diarrhea, dizziness, and vomiting were more common in the difelikefalin group than in the placebo group.. Patients treated with difelikefalin had a significant reduction in itch intensity and improved itch-related quality of life as compared with those who received placebo. (Funded by Cara Therapeutics; KALM-1 ClinicalTrials.gov number, NCT03422653.).

Topics: Adult; Double-Blind Method; Female; Humans; Kidney Failure, Chronic; Male; Middle Aged; Piperidines; Pruritus; Quality of Life; Receptors, Opioid; Renal Dialysis; Treatment Outcome; Uremia

To evaluate the efficacy of orvepitant (10 or 30 mg given once daily, orally for 4 weeks), a neurokinin-1 receptor antagonist, compared with placebo in reducing the intensity of epidermal growth factor receptor inhibitor (EGFRI)-induced intense pruritus.. Randomised, double-blind, placebo-controlled clinical trial.. 15 hospitals in Italy and five hospitals in the UK.. 44 patients aged ≥18 years receiving an EGFRI for a histologically confirmed malignant solid tumour and experiencing moderate or intense pruritus after EGFRI treatment.. 30 or 10 mg orvepitant or placebo tablets once daily for 4 weeks (randomised 1:1:1).. The primary endpoint was change from baseline in mean patient-recorded numerical rating scale (NRS) score (over the last three recordings) at week 4. Secondary outcome measures were NRS score, verbal rating scale score, Skindex-16 and Leeds Sleep Evaluation Questionnaire at each study visit (baseline, weeks 1, 4, 8); rescue medication use; EGFRI dose reduction; and study withdrawal because of intense uncontrolled pruritus.. The trial was terminated early because of recruitment challenges; only 44 of the planned 90 patients were randomised. All patients were analysed for efficacy and safety. Mean NRS score change from baseline to week 4 was -2.78 (SD: 2.64) points in the 30 mg group, -3.04 (SD: 3.06) points in the 10 mg group and -3.21 (SD: 1.77) points in the placebo group; the difference between orvepitant and placebo was not statistically significant. No safety signal was detected. Adverse events related to orvepitant (asthenia, dizziness, dry mouth, hyperhidrosis) were all of mild or moderate severity.. Orvepitant was safe and well tolerated. No difference in NRS score between the orvepitant and placebo groups was observed at the week 4 primary endpoint. A number of explanations for this outcome are possible.. EudraCT2013-002763-25.

Topics: Adult; Aged; Aged, 80 and over; Antidepressive Agents; Bridged Bicyclo Compounds, Heterocyclic; Dose-Response Relationship, Drug; Double-Blind Method; Early Termination of Clinical Trials; Female; Humans; Italy; Male; Middle Aged; Neoplasms; Neurokinin-1 Receptor Antagonists; Piperidines; Pruritus; Severity of Illness Index; United Kingdom

A number of second-generation non-sedating antihistamines are used in clinical practices over the world. However, long-term safety and efficacy have not been proved high level evidence based medicine. We have performed an open-label, multicenter, phase III study to evaluate the long-term safety and efficacy of bilastine, a novel non-sedating H

Topics: Adult; Benzimidazoles; Chronic Disease; Eczema; Female; Histamine H1 Antagonists, Non-Sedating; Humans; Japan; Long Term Adverse Effects; Male; Middle Aged; Piperidines; Prurigo; Pruritus; Quality of Life; Severity of Illness Index; Treatment Outcome; Urticaria

Tofacitinib is an oral Janus kinase inhibitor that improves clinical measures of psoriasis.. We sought to assess patient-reported outcomes in tofacitinib-treated patients with moderate to severe plaque psoriasis over 52 weeks.. In 2 identical, phase III studies (Oral treatment for Psoriasis Trial Pivotal 1 [NCT01276639], n = 901, and Pivotal 2 [NCT01309737], n = 960), patients were randomized 2:2:1 to receive 5 or 10 mg of tofacitinib or placebo, twice daily. At week 16, placebo-treated patients were re-randomized to tofacitinib. Dermatology Life Quality Index score, Itch Severity Item score, Patient Global Assessment score, and patient satisfaction were assessed.. Baseline Dermatology Life Quality Index score indicated substantial health-related quality of life impairment. At week 16, a greater proportion of patients achieved Dermatology Life Quality Index score of 1 or less (no effect of psoriasis on health-related quality of life) with tofacitinib 5 and 10 mg twice daily versus placebo (Oral treatment for Psoriasis Trial Pivotal 1/2: 26.7%/28.6% and 40.2%/48.2% vs 4.6%/6.0%, respectively; P < .0001); improvements were maintained through week 52. Similar patterns were observed with Patient Global Assessment. Improvements in itch were particularly rapid, observed 1 day after treatment initiation for both tofacitinib doses versus placebo (P < .05). At week 16, more patients were satisfied with tofacitinib versus placebo (P < .0001).. Clinical nonresponders discontinued at week 28.. Tofacitinib demonstrated improvement in health-related quality of life and patient-reported symptoms that persisted over 52 weeks.

Topics: Adult; Female; Humans; Male; Middle Aged; Pain; Patient Satisfaction; Piperidines; Protein Kinase Inhibitors; Pruritus; Psoriasis; Pyrimidines; Pyrroles; Quality of Life; Severity of Illness Index

Tofacitinib is a novel, oral Janus kinase inhibitor being investigated for psoriasis. This study assessed the relationship between pruritus and clinical signs of psoriasis (assessed by Physician's Global Assessment [PGA]) in patients with moderate-to-severe chronic plaque psoriasis receiving tofacitinib.. In this 16-week (12-week treatment period, 4-week observation period), double-blind, placebo-controlled, phase IIb study (NCT00678210), 197 patients were randomized to tofacitinib 2, 5 or 15 mg BID, or placebo. Pruritus was patient assessed using the Itch Severity Score (ISS), a 0-10 (10=worst itching) rating scale recorded daily from baseline to week 2 and at study visits. Mediation modeling was used to determine relationships between ISS (average score weeks 2-12), PGA (average score weeks 2-12) and treatment groups.. Mediation analysis showed that 70.2-80.5% (p<0.001 versus placebo) of tofacitinib's effect on pruritus was direct, and mostly independent of improvements in erythema, induration and scaling. ISS measurements had acceptable test-retest reliability. Correlation analyses with clinical outcomes supported the validity of the ISS as a pruritus measure.. Tofacitinib has a direct, beneficial effect on patient-reported pruritus independent from improvements in clinician-reported psoriasis severity signs. The ISS demonstrated favorable psychometric characteristics, supporting its use as a pruritus assessment tool.

Topics: Adult; Double-Blind Method; Female; Humans; Male; Middle Aged; Piperidines; Protein Kinase Inhibitors; Pruritus; Psoriasis; Psychometrics; Pyrimidines; Pyrroles; Reproducibility of Results; Treatment Outcome

The Itch Severity Score (ISS), a 0-10 numeric rating scale, was used to assess pruritus due to psoriasis in a Phase 2 b trial of tofacitinib, a novel oral Janus kinase inhibitor. 197 patients with moderate-to-severe plaque psoriasis were randomized to tofacitinib 2, 5 or 15 mg twice daily, or placebo. The ISS was recorded daily from baseline to week 2 and at study visits. Following good and recommended research practice, we performed analyses to examine the clinically important differences (CID) (between-group difference or within-group difference) and clinically important responders (CIR) (within-patient change) for the ISS. The CID and CIR were defined using Patient Global Assessment of psoriasis as an anchor and were estimated with a longitudinal model. A CID on the ISS was 1.64 and, by day 10, the mean changes from baseline in ISS values for the tofacitinib doses (placebo-adjusted) exceeded CID. A CIR on the ISS was a 30% improvement from baseline and, at week 12, 87.2% to 100% of patients receiving tofacitinib reached ≥30% improvement versus 29.4% of patients receiving placebo (p < 0.0001). Overall, the CID and CIR analyses play vital roles in the interpretation of the treatment effects measured by ISS.

Topics: Double-Blind Method; Humans; Piperidines; Pruritus; Psoriasis; Pyrimidines; Pyrroles; Treatment Outcome

Trikatu is composed of dried fruits of Piper nigrum L and Piper retrofractum Vahl, and dried rhizomes of Zingiber officinale R. Although this preparation has been used to relieve pruritis, pain, and inflammation for a long time, there is no clinical evidence to confirm its efficacy and safety. Therefore, we performed a double-blind, within person-randomized controlled study of 30 healthy volunteers to determine efficacy and safety of topical Trikatu on mosquito bite reactions.. All subjects were bitten by Aedes aegypti laboratory mosquitoes on their forearms and they were randomly assigned arms to apply either Trikatu or reference product on the mosquito bite papule. The main outcome was the difference of papule size reduction at 30 min, measured by a caliper, between the Trikatu and reference arms. Pruritis, redness, pain, and patient satisfaction were assessed at 15, 30, 60, 180, and 360 min as secondary outcomes.. There were no significant differences between treatment and reference arms on any outcome at any time of measurement.. Trikatu did not show additional effects for relieving mosquito bite reaction as compared with the reference product containing camphor, menthol, and eucalyptus. For further study, it is very important to consider a proper selection of subjects, comparator product, and concentration of extract when Trikatu preparation is investigated.

Topics: Adult; Aedes; Alkenes; Animals; Erythema; Female; Humans; Insect Bites and Stings; Male; Piperidines; Plant Extracts; Pruritus

This trial aimed to compare the maternal and neonatal effects of remifentanil given by patient-controlled analgesia (PCA) or continuous infusion for labour analgesia. Patient controlled analgesia was administered using increasing stepwise boluses from 0.1 to 0.4 μg.kg(-1) (0.1 μg.kg(-1) increment, 2 min lockout, n = 30). Continuous infusion used rates from 0.05 to 0.2 μg.kg(-1) .min(-1) (0.05 μg.kg(-1) .min(-1) increment, n = 30). Dose increments were given on request. Women reported lowest pain scores (median (IQR [range]) of 3 (2-4 [2-5]) for PCA and 4 (3-5.25 [3-7]) for continuous infusion (p = 0.004) at 60 min after the beginning of analgesia. The mean (SD) remifentanil umbilical vein/maternal artery ratio in the PCA and infusion groups were 0.74 (0.45) vs 0.70 (0.52), respectively (p = 0.776). The mean (SD) umbilical artery/umbilical vein ratios were 0.31 (0.12) vs 0.26 (0.07), respectively (p = 0.088). Maternal and neonatal adverse reactions of remifentanil were similar between the two groups. The total remifentanil consumption (median (IQR [range]) during PCA administration was lower than continuous infusion, 1.34 (1.22-1.48 [0.89-1.69]) mg vs 1.49 (1.35-1.61 [1.12-1.70] mg; p = 0.011). The results suggest that remifentanil PCA provides better pain relief and similar placental transfer compared with continuous infusion.

Topics: Adult; Analgesia, Obstetrical; Analgesia, Patient-Controlled; Analgesics, Opioid; Analysis of Variance; Blood Pressure; Bradycardia; Double-Blind Method; Female; Fetal Heart; Heart Rate; Humans; Infusions, Intravenous; Maternal-Fetal Exchange; Nausea; Pain Measurement; Patient Satisfaction; Piperidines; Pregnancy; Prospective Studies; Pruritus; Remifentanil; Treatment Outcome; Young Adult

This clinical trial evaluated the safety and effectiveness of bepotastine besilate ophthalmic solutions 1.0% and 1.5% compared with placebo for the treatment of ocular itching and conjunctival hyperemia (redness) using the conjunctival allergen challenge (CAC) model of allergic conjunctivitis when dosed 16 h before a CAC test.. Subjects with a history of allergic conjunctivitis were assigned to receive placebo or bepotastine besilate ophthalmic solution 1.0% or 1.5% in a single-center, randomized, placebo-controlled clinical trial. Eligible subjects (n=107) aged 10 years and older with a history of allergic conjunctivitis who had a reproducible positive reaction to a CAC were enrolled and dosed with test agent. The primary trial objectives included assessment of ocular itching and conjunctival redness at 16 h after instillation of test agent. Reductions in several CAC-induced secondary symptoms and signs of allergic conjunctivitis were also evaluated for tearing, ciliary and episcleral redness, eyelid swelling, chemosis, and mucous discharge.. Bepotastine besilate ophthalmic solution 1.5% demonstrated clinical effectiveness and statistical significance in comparison to placebo for the reduction in CAC-induced ocular itching 16 h after drug administration. Bepotastine besilate ophthalmic solution 1.0% also achieved statistical significance in comparison to placebo for reducing ocular itching at all time points 16 h after dosing. Statistically significant reduction (P≤0.05) was additionally seen in this CAC test for the secondary ocular efficacy variable of allergen-induced tearing for bepotastine besilate ophthalmic solution 1.5%. No clinical benefit was seen for reducing the coprimary efficacy variable of conjunctival redness with the CAC model of allergic conjunctivitis.. Bepotastine besilate ophthalmic solution 1.5% produced predefined clinically meaningful reduction in CAC-induced ocular itching and tearing in a single-site trial and was more effective than bepotastine besilate ophthalmic solution 1.0% and placebo for reducing ocular itching in a CAC test 16 h after dosing.

Topics: Adolescent; Adult; Aged; Anti-Allergic Agents; Child; Conjunctiva; Conjunctivitis, Allergic; Dose-Response Relationship, Drug; Double-Blind Method; Female; Humans; Hyperemia; Male; Middle Aged; Ophthalmic Solutions; Piperidines; Prospective Studies; Pruritus; Pyridines; Time Factors; Young Adult

To compare the analgesic efficacy of remifentanil with meperidine and fentanyl in a patient-controlled setting (patient-controlled analgesia, PCA).. Parturients (n=159) were randomly assigned to receive remifentanil (n=52), meperidine (n=53), or fentanyl (n=54). Pain scores and an observer sedation scores were assessed hourly. Fetal outcome was evaluated with Apgar score, cord blood gas analysis and the Neurologic and Adaptive Capacity Score.. Pain scores decreased in all groups, the decrease varying from mild to moderate, average pain scores remaining above 4.5 cm in all groups. Remifentanil PCA was associated with the greatest decrease in pain scores, but the difference was significant only at 1 h. Pain scores returned towards baseline over time; 3 h after the initiation of treatment, pain scores no longer differed significantly from baseline values in any of the groups. Significantly more parturients receiving meperidine crossed over to epidural analgesia. Overall satisfaction scores were higher with remifentanil, but remifentanil produced more sedation and itching. More periods of desaturation (Sa(o(2)) <95%) were observed during administration of remifentanil and fentanyl. There were no significant differences in fetal outcome between the three groups.. The efficacy of meperidine, fentanyl, and remifentanil PCA for labour analgesia varied from mild to moderate. Remifentanil PCA provided better analgesia than meperidine and fentanyl PCA, but only during the first hour of treatment. In all groups, pain scores returned to pre-treatment values within 3 h after the initiation of treatment.

Topics: Adult; Analgesia, Obstetrical; Analgesia, Patient-Controlled; Analgesics, Opioid; Consciousness; Double-Blind Method; Female; Fentanyl; Humans; Meperidine; Oxygen; Pain Measurement; Patient Satisfaction; Piperidines; Pregnancy; Pregnancy Outcome; Pruritus; Remifentanil

Bepotastine besilate is a highly selective histamine H(1)-receptor antagonist with antihistaminic, mast cell stabilizing, and anti-inflammatory activity. Based on a history of clinical effectiveness and tolerability of oral bepotastine besilate in the treatment of allergic symptoms, bepotastine besilate is being tested as a potential ophthalmic medication for allergic conjunctivitis.. The aim of this study was to assess the effects of bepotastine besilate ophthalmic solution 1.0% and 1.5% for the treatment of ocular itching and conjunctival hyperemia in a conjunctival allergen challenge (CAC) model in adults and children.. This Phase III, single-center, prospective, randomized, double-masked, placebo-controlled, CAC clinical trial enrolled patients >or=10 years of age with a history of allergic conjunctivitis, skin-test reaction, and CAC response. Patients received bepotastine besilate ophthalmic solution 1.0%, bepotastine besilate ophthalmic solution 1.5%, or placebo, 1 drop on each eye on days 14 +/- 3 and 28 +/- 3. The primary efficacy end points, patient-assessed ocular itching (at 3, 5, and 7 minutes) and investigator-assessed conjunctival hyperemia (at 7, 15, and 20 minutes), were determined after CAC according to standardized 5-point scales (0 = none to 4 = severe). Clinical significance was defined in the protocol as >or=1.0-U between-group difference in mean ocular itching scores at the majority of time points at a study visit and also a >or=0.5-U difference at all time points. Tolerability of the test agent was assessed by visual acuity, slit-lamp biomicroscopy, intraocular pressure, dilated funduscopy, and adverse events.. A total of 107 patients (male, 54%; age range, 11-73 years; white race/ethnicity, 93%) received investigational product and comprised the intent-to-treat (ITT) population (bepotastine besilate ophthalmic solution 1.0%, 36 patients; bepotastine besilate ophthalmic solution 1.5%, 35; and placebo, 36). All 107 patients received investigational product at visit 3A (day 0) and were included in the ITT population. Of the 107 patients who were enrolled, 103 completed the study without a protocol deviation or violation. The 1.0% and 1.5% solutions were associated with clinically and statistically significant reductions in mean ocular itching scores compared with placebo on the 15-minute onset-of-action and 8-hour duration-of-action CAC tests (reductions, 1.3-1.5 U and 1.0-1.7 U respectively; all, P < 0.001). Statistically significant reductions in conjunctival hyperemia were achieved with both bepotastine besilate concentrations. Overall, 13 patients experienced a treatment-emergent adverse event considered related to the study drug (bepotastine besilate ophthalmic solution 1.0%, 6 patients; bepotastine besilate ophthalmic solution 1.5%, 4; and placebo, 3).. In this CAC model of allergic conjunctivitis in adults and children, bepotastine besilate ophthalmic solutions 1.0% and 1.5% were associated with clinically and statistically significant reductions in ocular itching, but not conjunctival hyperemia, within 15 minutes that were maintained for at least 8 hours after administration. Both solutions were well tolerated. ClinicalTrials.gov identifier: NCT00424398.

Topics: Administration, Topical; Adolescent; Adult; Aged; Allergens; Anti-Allergic Agents; Child; Conjunctivitis, Allergic; Dose-Response Relationship, Drug; Double-Blind Method; Female; Humans; Male; Middle Aged; Ophthalmic Solutions; Piperidines; Prospective Studies; Pruritus; Pyridines; Severity of Illness Index; Time Factors; Treatment Outcome; Young Adult

Ebastine is a long-acting, second-generation, selective histamine H1-receptor antagonist. A fast-dissolving tablet formulation of ebastine has been developed at 10- and 20-mg doses, with the intention of facilitating administration to patients experiencing problems with swallowing, including those confined to bed and elderly people, as well as those who may need to use ebastine when they do not have easy access to water to aid swallowing a tablet.. This study was conducted to assess the pharmacodynamic effects (ie, inhibition of wheal response to cutaneous histamine challenge, and subjective assessments of itching, flare, and pain) and tolerability of the fast-dissolving 20-mg ebastine tablet formulation compared with desloratadine 5-mg capsule and placebo. Acceptability and convenience of the fast-dissolving tablet were also evaluated.. This double-blind, double-dummy, randomized, placebo-controlled, 3-period crossover study was conducted at the Drug Research Centre, Department of Clinical Pharmacology, the Hospital de la Santa Creu i Sant Pau, Barcelona, Spain. Healthy, nonatopic, white adults aged 18 to 40 years were randomly assigned to 1 of 6 study sequences: ABC, ACB, BAC, BCA, CBA, or CAB, where A was the ebastine fast-dissolving 20-mg tablet, B was the desloratadine 5-mg capsule, and C was placebo. All study drugs were given orally once daily (8-9 AM) on days 1 to 5 of each study period. Study periods were separated by a washout period of 7 to 10 days. Histamine skin-prick test (SPT) challenge was performed before study drug administration on day 1 of each period (baseline), and then every 20 minutes for 2 hours after administration and again after 24 hours. The final SPT was 24 hours after the day-5 dose was administered. The primary end point was inhibition o f the histamine response, defined as the percentage reduction from baseline wheal area 24 hours after 5 days of administration. Subjective symptoms (itching, flare, and pain) were assessed by subjects using visual analog scales every 20 minutes for 2 hours after administration on day 1. At study end, acceptability (taste, convenience, and overall preference) of the fast-dissolving tablet and capsule formulations were assessed using a questionnaire completed by subjects. Tolerability was assessed using physical examination, laboratory analysis, physician questioning, and spontaneous reporting.. Thirty-six people were randomized (22 women, 14 men; mean [SD] age, 24.7 [4.1] years; mean [SD] weight, 63.2 [9.9] kg); 35 completed the study (1 subject was lost to follow-up after the second study period). Unadjusted mean (SD) wheal areas 24 hours after dose administration on day 5 were 72.9 (29.5), 115.0 (32.1), and 146.7 (32.2) mm(2), for ebastine, desloratadine, and placebo, respectively. Mean differences in reduction from baseline in wheal area were 29.0% for ebastine versus desloratadine and 43.7% for ebastine versus placebo (both, P < 0.001). Corresponding unadjusted mean (SD) wheal areas 24 hours after administration of the first dose on day 1 were 76.5 (22.5), 128.9 (24.0), and 140.5 (33.1) mm(2). Mean itching, flare, and pain ratings were not significantly different between study drugs. Results from the preference questionnaire indicated that the majority (80%) preferred the ebastine fast-dissolving tablet to the desloratadine capsule (and hypothetically also to tablets and oral solution, which were not tested in this study). Ninety-seven percent of subjects were of the opinion that compliance in the home setting would be facilitated by the fas-tdissolving tablet formulation. Fourteen adverse events (AEs) were reported in 9 (25%) volunteers; all AEs were of mild or moderate intensity. Five occurred with ebastine 20 mg (intermittent somnolence, back pain, pharyngolaryngeal pain, pyrexia, and oral pain [1 patient each]), 5 occurred with desloratadine 5 mg (asthenia [2 patients] and dry mouth, somnolence, and back pain [1 patient each]), and 4 occurred with placebo (diarrhea [2 patients] and somnolence and headache [1 patient each]). The relationship with the study drugs was considered unlikely in 6 cases and possible in the remaining 8 cases. An additional AE (back pain) occurred during a washout period.. In this small study in healthy, nonatopic white subjects, inhibition of the response to histamine injection was significantly greater with the ebastine 20-mg fast-dissolving tablet compared with desloratadine 5-mg capsule and placebo after 1 and 5 days of administration. Most participants expressed an overall preference for the fast-dissolving tablet formulation over capsules. All study drugs were well tolerated.

Topics: Adolescent; Adult; Butyrophenones; Cross-Over Studies; Double-Blind Method; Female; Histamine; Histamine H1 Antagonists; Humans; Loratadine; Male; Pain Measurement; Piperidines; Pruritus; Skin; Skin Tests

Approximately 16.2% of the Japanese population suffer from cedar pollinosis, with various manifestations such as ophthalmic, laryngo-pharyngeal and skin symptoms in addition to nasal symptoms. Thus, the annual pollen season is an agonizing period for patients. No study has reported symptoms and their clinical courses after conjunctival provocation with purified cedar pollen allergen Cry j1 as well as suppression of these allergen-induced ocular symptoms by antihistamine eye drops.. Nine patients with Japanese cedar pollinosis who had no nasal or ocular symptoms were included in the present study, after obtaining informed consent in writing. 1) Purified cedar pollen allergen Cry j1 was instilled in the left eye and phosphate-buffered saline (PBS) in the right eye as a control. 2) Levocabastine hydrochloride ophthalmic suspension and ketotifen fumarate ophthalmic solution were respectively instilled in the left and right eyes, which were then challenged with the allergen. Ocular symptoms after provocation with the allergen were recorded through the clinical course.. Pollen allergen-induced ocular symptoms were itching and hyperemia of the palpebral conjunctiva, and itching lasted for more than 5 hours. Moreover, preadministration of antihistamine eye drops suppressed the increases in the ocular symptom scores, eliminating itching within 1 hour. Allergen provoked not only ocular symptoms but also nasal symptoms in 77.8% of patients.. Preadministration of antihistamine eye drops suppressed the symptoms induced by the allergen, which suggests that this is an effective early therapy for Japanese cedar pollinosis, if it is started before the pollen season. However, self-protection by patients using a mask may not be effective enough to suppress nasal symptoms during the pollen season, requiring them to additionally wear glasses to avoid exposure to the allergen.

Topics: Adult; Allergens; Antigens, Plant; Conjunctivitis, Allergic; Cryptomeria; Dose-Response Relationship, Immunologic; Histamine H1 Antagonists; Histamine H1 Antagonists, Non-Sedating; Humans; Hyperemia; Japan; Ketotifen; Ophthalmic Solutions; Piperidines; Plant Proteins; Pollen; Premedication; Pruritus; Rhinitis, Allergic, Seasonal; Severity of Illness Index; Treatment Outcome

This randomized, double-blind study was designed to evaluate analgesic effectiveness and side effects of two remifentanil infusion rates in patients undergoing extracorporeal shock wave lithotripsy (ESWL) for renal stones. We included 200 patients who were administered remifentanil either 0.05 microg x kg(-1) x min(-1) (n = 100) or 0.1 microg x kg(-1) x min(-1) (n = 100) plus demand bolus of 10 microg of remifentanil via a patient-controlled analgesia (PCA) device. No other sedating drugs were given. The frequencies of PCA demands and deliveries were recorded. Arterial blood pressure, oxygen saturation, and respiratory rate were recorded throughout the procedure; postoperative nausea and vomiting (PONV), dizziness, itching, agitation, and respiratory depression were measured posttreatment. Visual analog scale (VAS) scores were taken preoperatively, directly postoperatively, and 30 min after finishing the procedure. There were no statistically significant differences in the frequency of PCA demands and delivered boluses or among perioperative VAS scores. The extent of PONV and frequency of dizziness and itching immediately after and dizziness 30 min after the end of treatment were significantly reduced in the smaller dose group. We conclude that a remifentanil regimen of 0.05 microg x kg(-1) x min(-1) plus 10 microg demands is superior to 0.1 microg x kg(-1) x min(-1) plus demands, as there was no difference in the VAS scores recorded between groups and it has a less frequent incidence of side effects in patients receiving ESWL.. Remifentanil is an appropriate analgesic choice for patients undergoing extracorporeal shock wave lithotripsy (ESWL) therapy, as it has both fast onset and offset times. We studied remifentanil as a sole drug for ESWL and have shown that an infusion rate of 0.05 microg x kg-1 x min-1 plus patient-controlled analgesia demands of 10 microg provides adequate analgesia and has significantly less side effects than a dose of 0.1 microg x kg-1 x min-1 plus 10 microg demands.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Analgesia, Patient-Controlled; Analgesics, Opioid; Dizziness; Dose-Response Relationship, Drug; Female; Humans; Infusions, Intravenous; Kidney Calculi; Lithotripsy; Male; Middle Aged; Pain Measurement; Piperidines; Postoperative Complications; Postoperative Nausea and Vomiting; Pruritus; Remifentanil; Single-Blind Method

Remifentanil has been suggested as an ideal opioid for patient-controlled analgesia (PCA) in labour, but the safety profile has not been established. The aims of this preliminary prospective observational study were to investigate the maternal side-effects and early neonatal effects, and to assess the placental transfer of remifentanil PCA during labour.. Women with no known obstetric complications or contraindication to remifentanil were recruited (n=50). Remifentanil was administered at a bolus dose of 0.5 microg kg(-1) and a lockout period of 2 min. A visual analogue scale was used to assess pain, nausea and itching. Maternal observations were recorded hourly and fetal heart rate trace was assessed every 2 h. Umbilical cord gases, 1 and 5 min Apgar scores and neurological evaluation of the neonate were recorded. Maternal venous blood and umbilical artery and vein cord blood samples were collected for analysis of remifentanil concentration.. Fifty women enrolled in the study (24 multiparous, 26 primiparous). There was no evidence of cardiovascular instability or respiratory depression. Pain scores decreased significantly, but there was no significant change in nausea after initiating the PCA. A statistically significant increase in itching was found to be clinically mild and 22 women were slightly drowsy (95% confidence interval [CI], 30-58.7%) but alert to voice. Ten fetal heart rate traces demonstrated changes in the first 20 min, but did not require intervention (95% CI, 10-33.7%). The median 1 and 5 min Apgar scores were 9. The mean umbilical cord gases and neurological examination were within normal limits. Maternal vein and umbilical vein cord samples demonstrated placental transfer of remifentanil, and small amounts were detected in umbilical artery samples.. At the bolus dose used remifentanil PCA has an acceptable level of maternal side-effects and minimal effect on the neonate. Remifentanil crosses the placenta and appears to be either rapidly metabolized or redistributed in the neonate.

Topics: Adolescent; Adult; Analgesia, Obstetrical; Analgesia, Patient-Controlled; Analgesics, Opioid; Apgar Score; Female; Fetal Heart; Humans; Infant, Newborn; Maternal-Fetal Exchange; Nausea; Piperidines; Pregnancy; Prospective Studies; Pruritus; Remifentanil

Posture has an effect on gastric emptying. In this study, we investigated whether posture influences the delay in gastric emptying induced by opioid analgesics. Ten healthy male subjects underwent 4 gastric emptying studies with the acetaminophen method. On two occasions the subjects were given a continuous infusion of remifentanil (0.2 microg. kg(-1). min(-1)) while lying either on the right lateral side in a 20 degrees head-up position or on the left lateral side in a 20 degrees head-down position. On two other occasions no infusion was given, and the subjects were studied lying in the two positions. When remifentanil was given, there were no significant differences between the two postures in maximal acetaminophen concentration (right side, 34 micromol. L(-1); versus left side, 16 micromol. L(-1)), time taken to reach the maximal concentration (94 versus 109 min), or area under the serum acetaminophen concentration time curve from 0 to 60 min (962 versus 197 min. micromol. L(-1)). In the control situation, there were differences between the postures in maximal acetaminophen concentration (138 versus 94 micromol. L(-1); P < 0.0001) and area under the serum acetaminophen concentration time curves from 0 to 60 min (5092 versus 3793 min. micromol. L(-1); P < 0.0001), but there was no significant difference in time taken to reach the maximal concentration (25 versus 47 min). Compared with the control situation, remifentanil delayed gastric emptying in both postures. We conclude that remifentanil delays gastric emptying and that this delay is not influenced by posture.

Topics: Acetaminophen; Adult; Analgesics, Non-Narcotic; Analgesics, Opioid; Area Under Curve; Blood Gas Analysis; Blood Pressure; Dose-Response Relationship, Drug; Gastric Emptying; Heart Rate; Humans; Male; Nausea; Piperidines; Posture; Pruritus; Remifentanil; Respiratory Mechanics; Vomiting

People frequently experience whealing and delayed papules from mosquito bites. Whealing is mediated by antisaliva immunoglobulin (Ig)E antibodies and histamine. Cetirizine, ebastine and loratadine have earlier shown effects on mosquito-bite reactions but no comparative studies exist.. A double-blind, placebo-controlled, cross-over study was performed with cetirizine 10 mg, ebastine 10 mg and loratadine 10 mg in 29 mosquito-bite-sensitive adults exposed to Aedes aegypti mosquito-bites. The size of the bite lesion and the intensity of pruritus (visual analog scale) were measured at 15 min and 2, 6 and 24 h.. Cetirizine and ebastine, but not loratadine, decreased significantly the size of whealing (P < 0.01) and accompanying pruritus (P < 0.001) compared to placebo. Cetirizine was most effective on pruritus but caused more often sedation than ebastine or loratadine. The delayed bite symptoms remained too faint for any statistical comparison.. This comparative study in mosquito-bite-sensitive adults shows that cetirizine and ebastine decrease significantly whealing and accompanying pruritus, and that cetirizine seems to be the most effective against pruritus.

Topics: Adult; Animals; Butyrophenones; Cetirizine; Conscious Sedation; Cross-Over Studies; Culicidae; Double-Blind Method; Finland; Histamine H1 Antagonists; Humans; Hypersensitivity, Immediate; Insect Bites and Stings; Loratadine; Middle Aged; Piperidines; Pruritus; Severity of Illness Index; Time Factors; Treatment Outcome

The efficacy and safety of emedastine 0.05% eye drops (Emadine; Alcon Laboratories, Inc, Fort Worth, Texas), a new H(1) antagonist, were studied in comparison to levocabastine 0.05% eye drops (Livostin; Janssen-Cilag N V, Berchem, Belgium) during a twice-daily treatment schedule for 6 weeks in adult and pediatric patients with seasonal allergic conjunctivitis.. In a prospective, multicenter, randomized, double-masked, parallel group study, 222 patients with allergic conjunctivitis were randomized (221 received treatment) to either emedastine or levocabastine, instilled twice daily for 6 weeks. Patient diaries were completed four times daily (before the morning and evening instillations, at noon, and in the afternoon), and clinical examinations were conducted at regular intervals. Primary efficacy variables of ocular redness and itching and secondary efficacy variables of chemosis, eyelid swelling, patient diary data, and physician's global assessment were analyzed.. Both emedastine and levocabastine produced a statistically significant (P =.0001) reduction in itching and redness within 5 minutes of the first instillation. All signs and symptoms improved progressively over the 6-week treatment period. After 7 days of use, and throughout the remainder of the study, emedastine was statistically superior to levocabastine (P <.006) in preventing and alleviating the signs and symptoms (itching, redness, chemosis, and eyelid swelling) of allergic conjunctivitis.. Emedastine 0.05% eye drops administered twice daily are more efficacious than levocabastine 0.05% eye drops in the prevention and treatment of the signs and symptoms of allergic conjunctivitis in adults and children of 4 years and above. Both emedastine 0.05% eye drops and levocabastine 0.05% eye drops were well tolerated.

Topics: Adolescent; Adult; Aged; Benzimidazoles; Child; Child, Preschool; Conjunctivitis, Allergic; Double-Blind Method; Drug Administration Schedule; Female; Histamine H1 Antagonists; Humans; Middle Aged; Ophthalmic Solutions; Piperidines; Prospective Studies; Pruritus

Remifentanil, an ultra-short-acting opioid analgesic, may be useful as an intravenous adjuvant to local anesthesia for treating patient discomfort and pain during monitored anesthesia care (MAC). However, the remifentanil dose requirements, interactions with other commonly used sedative drugs (such as midazolam), and recovery characteristics after ambulatory procedures have not been determined. Therefore, this study was designed to evaluate the safety and efficacy of remifentanil alone and in combination with different doses of midazolam during MAC.. Eighty-one healthy consenting women scheduled for elective breast biopsy procedures were randomly assigned to one of four treatment groups according to an institutional review board-approved, double-blind, placebo-controlled protocol. The study medication (containing either saline or 2 mg, 4 mg, or 8 mg of midazolam) was administered intravenously 5 min before starting an infusion of remifentanil at 0.1 microgram.kg-1.min-1. The remifentanil infusion was subsequently adjusted in 0.025- and 0.05-microgram.kg-1.min-1 increments to maintain patient comfort and adequate ventilation during the operation. The level of sedation was assessed at 1- to 10-min intervals during the procedure using the inverted observer's assessment of alertness/sedation (OAA/S) scale, with a score of 1 = awake, alert to 5 = asleep, unarousable. Discomfort and pain were assessed using numerical rating scales. Hemoglobin oxygen saturation, respiratory rate, blood pressure (systolic, diastolic, mean), and heart rate were monitored at 1- to 5-min intervals. Intraoperative amnesia was assessed by asking patients to recall a picture shown 5 min after the study medication was administered. Recovery was evaluated using the Aldrete score and the times to "home readiness" and actual discharge. Side effects and patient satisfaction were assessed in a follow-up telephone interview on the first postoperative day.. Midazolam produced dose-dependent increases in the median level of sedation. Remifentanil produced a greater reduction in respiratory rate in the 4-mg and 8-mg midazolam groups. However, there were no significant differences in the hemodynamic variables or discharge times. Patients with OAA/S scores of 1 to 3 ("light" sedation) 5 min after the study medication experienced a greater incidence of intraoperative pruritus and postoperative nausea and vomiting (PONV) compared with those with OAA/S scores of 4 to 5 ("deep" sedation). Discharge times were prolonged for patients in the light sedation group in whom PONV developed.. Use of remifentanil alone for MAC did not provide optimal sedation during local anesthesia. However, 0.05 to 0.1 microgram.kg-1.min-1 remifentanil in combination with 2 mg midazolam given intravenously, provided effective sedation and analgesia during MAC in healthy patients classified as American Society of Anesthesiologists status 1 to 2. Midazolam also produced dose-dependent potentiation of remifentanil's depressant effect on respiratory rate. In outpatients receiving a combination of midazolam and remifentanil during local anesthesia, the level of sedation appears to influence the incidence of both intraoperative pruritus and PONV.

Topics: Adjuvants, Anesthesia; Adult; Analgesics, Opioid; Anesthesia Recovery Period; Anesthesia, Local; Dose-Response Relationship, Drug; Double-Blind Method; Drug Interactions; Female; Humans; Infusions, Intravenous; Midazolam; Middle Aged; Monitoring, Intraoperative; Piperidines; Pruritus; Remifentanil

Twenty-nine pruritic, atopic dogs were entered into a double-blind, placebo-controlled, crossover study to evaluate the efficacy of an investigational antiallergenic compound, AHR-13268. Fourteen dogs were evaluated by a veterinary dermatologist (at intervals) and the owner (daily). Fifteen dogs were evaluated only by the owner. The mean (+/- SE) owner scores for pruritus, erythema, and lesions with placebo treatment (higher score = worse signs) were 3.24 (+/- 0.12), 2.73 (+/- 0.12), and 2.61 (+/- 0.09), respectively. With drug treatment, the corresponding scores were 2.89 (+/- 0.12), 2.50 (+/- 0.12), and 2.25 (+/- 0.09). Scores for pruritus and lesions (but not erythema) were significantly better with drug treatment than with placebo treatment. Investigator scores showed similar trends, but the differences were not great enough to be statistically significant. Overall, 11/29 (38%) owners reported their dogs had moderate or better improvement from drug capsules, and 4/29 dogs (14%) improved on placebo capsules. A variety of adverse effects were reported following both drug (9/29 dogs) and placebo (8/29 dogs) capsule administration, but were mild and well tolerated. Results of this study indicate that AHR-13268 has potential for empiric treatment of allergic inhalant dermatitis in some dogs.

Topics: Analysis of Variance; Animals; Benzoates; Dermatitis, Atopic; Dog Diseases; Dogs; Double-Blind Method; Histamine H1 Antagonists; Piperidines; Pruritus; Regression Analysis; Surveys and Questionnaires

The new antihistamine, HC20-511 (Sandoz), was compared with Dimetinden (Fenistil retard) in a single-blind comparative study in 42 patients with dermatoses, 28 of whom suffered from chronic urticaria. HC20-511 had a better effect, especially in chronic urticaria, where pruritus, erythema and papules quickly disappeared. The effect appeared somewhat faster than and lasted as long as that of Dimetinden, although HC20-511 is not a retard-preparation unlike the Dimetinden preparation used for comparison. HC20-511 also caused less side effects.

Topics: Adolescent; Adult; Aged; Chronic Disease; Clinical Trials as Topic; Dimethindene; Drug Therapy, Combination; Female; Fumarates; Histamine H1 Antagonists; Humans; Male; Middle Aged; Piperidines; Pruritus; Skin Diseases; Thiophenes; Urticaria; Vomiting

Topics: Adolescent; Adult; Child; Child, Preschool; Chronic Disease; Delayed-Action Preparations; Dermatitis; Female; Follow-Up Studies; Histamine H1 Antagonists; Humans; Male; Middle Aged; Piperidines; Placebos; Pruritus; Tablets; Time Factors; Urticaria

Topics: Humans; Piperidines; Pruritus; Pyrimidines

This case report describes 26-year-old woman who had multiple clusters of pale-pink lichenoid papules since childhood and the accompanying itching was intense. Skin biopsy revealed obvious fissures had formed under the epidermis. The patient was diagnosed with epidermolysis bullosa pruriginosa and was successfully treated with tofacitinib.

Topics: Adult; Dermatologic Agents; Epidermolysis Bullosa Dystrophica; Female; Humans; Janus Kinase Inhibitors; Piperidines; Pruritus; Pyrimidines

Topics: Analgesics, Opioid; Antipruritics; Drug Interactions; Humans; Piperidines; Pruritus; Renal Dialysis; Renal Insufficiency, Chronic; Treatment Outcome

Topics: Dermatitis; Humans; Janus Kinases; Piperidines; Pruritus; Pyrimidines; Pyrroles

Topics: Aged; Arthritis, Rheumatoid; Chronic Disease; Female; Follow-Up Studies; Humans; Male; Middle Aged; Piperidines; Protein Kinase Inhibitors; Pruritus; Pyrimidines; Severity of Illness Index; Treatment Outcome

The Janus kinase 1/3 inhibitor tofacitinib has demonstrated an antipruritic effect in two phase III studies in psoriasis. However, the mechanisms behind this antipruritic effect are still unknown. We presently investigated whether tofacitinib affects spontaneous itch as well as expression of itch-related cytokines and epidermal nerve fiber density (ENFD) in the imiquimod-induced mouse model of psoriasis. Psoriasis-like skin lesions were produced by daily topical application of imiquimod to the back skin. Imiquimod treatment resulted in spontaneous scratching, which was significantly inhibited by tofacitinib treatment. Imiquimod treatment significantly increased mRNA expression of Il22, Il23, and Il31, reduced peptidergic ENFD, and increased nonpeptidergic ENFD compared to naive mice. Tofacitinib significantly decreased the expression of those cytokines and increased peptidergic ENFD without a significant effect on nonpeptidergic ENFD. Tofacitinib may inhibit psoriatic itch through inhibition of cytokine expression as well as modulation of epidermal innervation.

Topics: Animals; Antipruritics; Behavior, Animal; Disease Models, Animal; Imiquimod; Interleukin-22; Interleukin-23; Interleukins; Janus Kinase Inhibitors; Male; Mice, Inbred C57BL; Nerve Fibers; Piperidines; Pruritus; Psoriasis; Pyrimidines; Pyrroles; Skin

Uremic pruritus with elevated levels of calcium phosphate (CaP) in skin is a common symptom in patients with chronic kidney disease (CKD). In this study, we demonstrate that intradermal injection of CaP into mice triggered scratching by up-regulating the IL-6 in skin and phosphorylation of ERKs in dorsal root ganglion (DRG) in a dose-dependent manner. IL-6 is essential because the CaP-induced up-regulation of phosphorylated (p)-ERK in DRG was considerably reduced in the IL-6 knockout mice. Microarray analysis in conjunction with real-time PCR revealed a higher mRNA expression of Bruton's tyrosine kinase (BTK) gene in DRG after CaP injection. The inhibition of BTK by ibrutinib noticeably diminish the CaP-induced up-regulation of IL-6 and p-ERK in mice. A high amount of IL-6 was detected in itchy skin and blood of patients with CKD. The expressions of p-BTK and p-ERK in DRG primary cells reached maximum levels at 1 and 10 min, respectively, after treatment of recombinant IL-6 and were significantly reduced by treatment of IL-6 along with ibrutinib. The mechanism by which the CaP-induced pruritus mediated by the IL-6/p-BTK/p-ERK signaling was revealed.-Keshari, S., Sipayung, A. D., Hsieh, C.-C., Su, L.-J., Chiang, Y.-R., Chang, H.-C., Yang, W.-C., Chuang, T.-H., Chen, C.-L., Huang, C.-M. IL-6/p-BTK/p-ERK signaling mediates calcium phosphate-induced pruritus.

Topics: Adenine; Agammaglobulinaemia Tyrosine Kinase; Animals; Calcium Phosphates; Extracellular Signal-Regulated MAP Kinases; Female; Ganglia, Spinal; Gene Expression Profiling; Interleukin-6; Mice, Inbred C57BL; Mice, Knockout; Phosphorylation; Piperidines; Pruritus; Pyrazoles; Pyrimidines; Signal Transduction; Skin

Tofacitinib is an oral Janus kinase inhibitor. This post-hoc analysis aimed to investigate the psychometric properties of the Itch Severity Item (ISI), a numeric rating scale from 0 (no itching) to 10 (worst possible itching) for pruritus in psoriasis, and review the effect of tofacitinib on pruritus in patients with psoriasis participating in Phase 3 studies (N = 3,641). The ISI showed high test-retest reliability (intra-class correlation coefficient: 0.84). The clinically important difference was defined as a 1.48-point change, using Patient Global Assessment as an anchor. Mean changes from baseline in ISI scores with tofacitinib were significantly greater than placebo by Day 2 and exceeded the clinically important difference by Week 4 and Week 2 for tofacitinib 5 and 10 mg twice daily, respectively. The sound psychometric properties of the ISI as an assessment tool for pruritus in psoriasis were confirmed. Tofacitinib provided clinically meaningful improvements in psoriatic pruritus versus placebo.

Topics: Antipruritics; Clinical Trials, Phase III as Topic; Humans; Piperidines; Predictive Value of Tests; Pruritus; Psoriasis; Psychometrics; Pyrimidines; Pyrroles; Randomized Controlled Trials as Topic; Remission Induction; Reproducibility of Results; Severity of Illness Index; Surveys and Questionnaires; Time Factors; Treatment Outcome

Cannabinoids have been used for their analgesic and euphoric effects for millennia, but recently the antipruritic effects of cannabis have been discovered. Considering the similarities between pain and itch sensations, we hypothesized that cannabinoid receptors may play a role in the antipruritic effects of cannabinoids.. To analyse the role of the spinal cannabinoid receptors, CB1 and CB2, in the antipruritic effects of the cannabinoid agonist WIN 55,212-2.. Male Balb/c mice weighing 20-30 g were used. Scratching behaviour in the mice was produced by injection of serotonin 5 μg/50 μL intradermally into the nape of the neck. Scratching of the site of injection by the hind paws was video-recorded for 30 min. After testing different doses of WIN 55,212-2 [1, 3 and 10 mg/kg intraperitoneally (IP)], the effects of the CB1 receptor antagonist, AM-251 [1 μg/mouse administered intrathecally (IT)] and the CB2 receptor antagonist AM-630 (4 μg/mouse IT) on the antipruritic effects of WIN 55,212-2 were studied using a rotarod apparatus.. WIN 55,212-2 (1, 3 or 10 mg/kg IP) dose-dependently decreased serotonin-induced scratches. The receptor antagonist CB1 partially reversed the effects of WIN 55,212-2 (P < 0.05); whereas CB2 had no statistically significant effect. WIN 55,212-2 impaired motor function only at the highest dose given (10 mg/kg, P < 0.05).. Our findings support prior researches indicating that cannabinoids exert antipruritic effects. Moreover, our results show that the antipruritic effects of cannabinoids are partially mediated by spinal CB1 receptors.

Topics: Animals; Benzoxazines; Cannabinoid Receptor Agonists; Cannabinoid Receptor Antagonists; Dose-Response Relationship, Drug; Indoles; Male; Mice; Mice, Inbred BALB C; Morpholines; Naphthalenes; Piperidines; Pruritus; Pyrazoles; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Serotonin; Spinal Cord

Pruritus is the most common complication of intrathecal morphine; however, its exact molecular mechanism is unclear, and treatment is challenging. The analgesic effect of N-methyl-D-aspartate (NMDA) receptor antagonists and the morphine-associated increase in NMDA receptor activation suggest potential role of NMDA receptor in the spinal itch sensation. Male C57BL/6 mice were given intrathecal morphine to induce scratching behavior. The effects of NMDA, ketamine, ifenprodil and U0126 on morphine-induced pruritus and analgesia were evaluated also. The number of scratching responses was counted for 30 min post-injection to evaluate pruritus. A warm-water tail immersion assay was conducted before and until 120 min post-injection at 30-min intervals. Percent of maximal possible effect (%MPE) and area under curve (AUC) were calculated based on tail-flick latency to evaluate analgesic efficacy. Compared with control treatment, intrathecal morphine elicited an obvious scratching response and analgesic effect in a dose dependent manner. Ketamine (1 μg), ifenprodil (0.1 μg) and U0126 (0.1 μg and 1.0 μg) all significantly attenuated morphine induced scratches. Ifenprodil (0.1 μg) injection significantly prolonged the analgesic effect of intrathecal morphine. The ERK1/2 phosphorylation induced by intrathecal morphine was inhibited by ketamine, ifenprodil and U0126 as well. U0126 inhibited morphine-induced pruritus with no effect on its analgesia. Therefore, intrathecal coadministration of morphine with NMDA receptor antagonists ketamine and ifenprodil alleviated morphine-induced scratching. Intrathecal morphine increased ERK phosphorylation in the lumbar spinal dorsal horn, which may be related with morphine-induced pruritus, and was counteracted by NMDA receptor antagonists.

Topics: Analgesia; Animals; Butadienes; Extracellular Signal-Regulated MAP Kinases; Injections, Spinal; Ketamine; Male; Mice, Inbred C57BL; Morphine; Nitriles; Phosphorylation; Piperidines; Pruritus; Receptors, N-Methyl-D-Aspartate

We report four patients developing a late form of papulopustular rash induced by epidermal growth factor receptor inhibitors. These patients presented an unusual presentation of acneiform rash, characterized by late development (several months after treatment commenced), localization to the limbs with sparing of the face, and association with severe pruritus and Staphylococcus aureus superinfection in all cases. These clinical symptoms may suggest a distinct mechanism from the early acne-like rash frequently observed with these targeted anticancer therapies. Clinicians should be aware of this delayed adverse event, and we suggest the term 'late acneiform toxicity of EGFR inhibitors (LATE) syndrome' to permit better characterization of this clinical picture.

Topics: Adult; Aged; ErbB Receptors; Erlotinib Hydrochloride; Female; Humans; Male; Middle Aged; Piperidines; Protein Kinase Inhibitors; Pruritus; Quinazolines; Skin Diseases, Papulosquamous; Staphylococcal Infections; Staphylococcus aureus

Histamine H4 receptor has been confirmed to play a role in evoking peripheral pruritus. However, the ionic and intracellular signaling mechanism of activation of H4 receptor on the dorsal root ganglion (DRG) neurons is still unknown. By using cell culture and calcium imaging, we studied the underlying mechanism of activation of H4 receptor on the DRG neuron. Immepip dihydrobromide (immepip)-a histamine H4 receptor special agonist under cutaneous injection-obviously induced itch behavior of mice. Immepip-induced scratching behavior could be blocked by TRPV1 antagonist AMG9810 and PLC pathway inhibitor U73122. Application of immepip (8.3-50 μM) could also induce a dose-dependent increase in intracellular Ca(2+) ([Ca(2+)]i) of DRG neurons. We found that 77.8% of the immepip-sensitized DRG neurons respond to the TRPV1 selective agonist capsaicin. U73122 could inhibit immepip-induced Ca(2+) responses. In addition, immepip-induced [Ca(2+)]i increase could be blocked by ruthenium red, capsazepine, and AMG9810; however it could not be blocked by TRPA1 antagonist HC-030031. These results indicate that TRPV1 but not TRPA1 is the important ion channel to induce the DRG neurons' responses in the downstream signaling pathway of histamine H4 receptor and suggest that TRPV1 may be involved in the mechanism of histamine-induced itch response by H4 receptor activation.

Topics: Acetanilides; Acrylamides; Animals; Antipruritics; Bridged Bicyclo Compounds, Heterocyclic; Calcium; Capsaicin; Dose-Response Relationship, Drug; Ganglia, Spinal; Histamine Agonists; Imidazoles; Mice; Neurons; Piperidines; Pruritus; Purines; Receptors, G-Protein-Coupled; Receptors, Histamine; Receptors, Histamine H4; TRPV Cation Channels; Type C Phospholipases

The increase of endocannabinoid tonus by inhibiting fatty acid amide hydrolase (FAAH) or monoacylglycerol lipase (MAGL) represents a promising therapeutic approach in a variety of disease to overcome serious central side effects of exocannabinoids. Recent studies reported that systemic administration of FAAH and MAGL inhibitors produce antipruritic action. Dual FAAH/MAGL inhibitors have also been described to get enhanced endocannabinoid therapeutic effect. In this study, we examined and compared dose-related antipruritic effects of systemic (intraperitoneal; ip) or intrathecal (it) administration of selective FAAH inhibitor PF-3845 (5, 10, and 20 mg/kg, i.p.; 1, 5, and 10 µg, i.t.), MAGL inhibitor JZL184 (4, 20, and 40 mg/kg, i.p.; 1, 5, and 10 µg, i.t.) and dual FAAH/MAGL inhibitor JZL195 (2, 5, and 20 mg/kg, i.p.; 1, 5, and 10 µg, i.t.) on serotonin (5-HT)-induced scratching model. Serotonin (25 μg) was injected intradermally in a volume of 50 μl into the rostral part of skin on the back of male Balb-C mice. Both systemic or intrathecal administration of PF-3845, JZL184 or JZL195 produced similar dose-dependent antipruritic effects. Our results suggest that endocannabinoid-degrading enzymes FAAH and MAGL are involved in pruritic process at spinal level. FAAH, MAGL or dual FAAH/MAGL inhibitors have promising antipruritic effects, at least, in part through spinal site of action.

Topics: Amidohydrolases; Animals; Antipruritics; Benzodioxoles; Carbamates; Disease Models, Animal; Endocannabinoids; Injections, Intraperitoneal; Injections, Spinal; Male; Mice; Mice, Inbred BALB C; Monoacylglycerol Lipases; Piperazines; Piperidines; Pruritus; Pyridines; Serotonin

Itch and pain are two irritating sensations sharing a lot in common. Considering the antinociceptive effects of blockade of endocannabinoid degrading enzymes in pain states, we attempted to reduce scratching behavior by endocannabinoid modulation, i.e. by inhibiting fatty acid amide hydrolase (FAAH), monoacylglycerol lipase (MAGL), or cellular uptake of endocannabinoids. Scratching behavior was induced by intradermal injection of serotonin to Balb/c mice. URB597 (10 mg/kg, i.p.), a FAAH inhibitor, JZL184 (16 mg/kg, i.p.), a MAGL inhibitor, and AM404 (10 mg/kg, i.p.), an endocannabinoid transport inhibitor, were given to evaluate the effects of endocannabinoid modulation on scratching responses. Then, the CB1 receptor antagonist, AM251 (1 mg/kg, i.p.), and the CB2 receptor antagonist, SR144528 (1 mg/kg, i.p.), were administered to determine whether cannabinoid receptors mediate these effects. URB597 and JZL184, but not AM404, attenuated serotonin-induced scratches. The inhibitory effect of URB597 was reversed by SR144528, but cannabinoid receptor antagonists had no other effects on modulation by the inhibitors. We propose that augmenting the endocannabinoid tonus by inhibition of degradative enzymes, FAAH and MAGL, but not cellular uptake, may be a novel target for the development of antipruritic agents.

Topics: Amidohydrolases; Animals; Arachidonic Acids; Benzamides; Benzodioxoles; Camphanes; Carbamates; Endocannabinoids; Enzyme Inhibitors; Male; Mice; Mice, Inbred BALB C; Monoacylglycerol Lipases; Piperidines; Pruritus; Pyrazoles; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Serotonin

The prevalence of allergic skin disorders has increased rapidly, and development of therapeutic agents to alleviate the symptoms are still needed. In this study, we orally or topically administered the Janus kinase (JAK) inhibitors, tofacitinib and oclacitinib, in a mouse model of dermatitis, and compared the efficacy to reduce the itch and inflammatory response. In vitro effects of JAK inhibitors on bone marrow-derived dendritic cells (BMDCs) were analyzed. For the allergic dermatitis model, female BALB/c mice were sensitized and challenged with toluene-2,4-diisocyanate (TDI). Each JAK inhibitor was orally or topically applied 30 minutes before and 4 hours after TDI challenge. After scratching bouts and ear thickness were measured, cytokines were determined in challenged skin and the cells of the draining lymph node were analyzed by means of flow cytometry. In vitro, both JAK inhibitors significantly inhibited cytokine production, migration, and maturation of BMDCs. Mice treated orally with JAK inhibitors showed a significant decrease in scratching behavior; however, ear thickness was not significantly reduced. In contrast, both scratching behavior and ear thickness in the topical treatment group were significantly reduced compared with the vehicle treatment group. However, cytokine production was differentially regulated by the JAK inhibitors, with some cytokines being significantly decreased and some being significantly increased. In conclusion, oral treatment with JAK inhibitors reduced itch behavior dramatically but had only little effect on the inflammatory response, whereas topical treatment improved both itch and inflammatory response. Although the JAK-inhibitory profile differs between both JAK inhibitors in vitro as well as in vivo, the effects have been comparable.

Topics: Administration, Oral; Administration, Topical; Animals; Anti-Inflammatory Agents; Antipruritics; Cytokines; Dermatitis, Allergic Contact; Disease Models, Animal; Female; Inflammation; Janus Kinases; Lymph Nodes; Mice; Mice, Inbred BALB C; Piperidines; Pruritus; Pyrimidines; Pyrroles; Skin; Sulfonamides

Janus kinase (JAK) inhibitors have recently been developed for allergic diseases. We focused on the 2 different JAK inhibitors, tofacitinib (selective for JAK3) and oclacitinib (selective for JAK1 and 2), to clarify the mechanism of anti-inflammatory and anti-itching potency of these drugs. In the process of detecting anti-itching potency, we observed that tofacitinib treated mice showed aggression behaviour. The objective of the study reported here was to investigate the aggressive behaviour induced by tofacitinib by using a mouse model of allergic dermatitis and the resident-intruder test. For the allergic dermatitis model, female BALB/c mice were sensitised and challenged topically with toluene-2,4-diisocyanate (TDI). Vehicle, tofacitinib or oclacitinib, was administered orally 30 min before TDI challenge. Scratching, aggression and standing behaviours were monitored in the 60 min period immediately following challenge of TDI. Another group of male BALB/c mice treated with vehicle, tofacitinib or oclacitinib was evaluated in the resident-intruder test and brains were obtained to determine blood brain barrier penetration. In the allergic dermatitis model, a significant increase in aggression and standing behaviour was only obvious in the tofacitinib treatment group. There was no effect in non-sensitised mice, but similar aggression was also induced by tofacitinib in male resident-intruder test. Penetration of blood-brain barrier was observed both in tofacitinib and oclacitinib treated mice. These results suggest that aggression was induced by tofacitinib under some kind of stressful environment. This study indicates a possible role of the JAK-STAT pathway in modulation of aggression behaviour.

Topics: Administration, Oral; Aggression; Animals; Anti-Allergic Agents; Anti-Inflammatory Agents; Behavior, Animal; Brain; Dermatitis, Atopic; Disease Models, Animal; Female; Janus Kinases; Male; Mice, Inbred BALB C; Piperidines; Protein Kinase Inhibitors; Pruritus; Pyrimidines; Pyrroles; Stress, Psychological; Sulfonamides; Toluene 2,4-Diisocyanate

We investigated roles for substance P (SP), gastrin-releasing peptide (GRP), and glutamate in the spinal neurotransmission of histamine-dependent and -independent itch. In anesthetized mice, responses of single superficial dorsal horn neurons to intradermal (i.d.) injection of chloroquine were partially reduced by spinal application of the α-amino-3-hydroxy-5-methyl-4-isoxazole proprionate acid (AMPA)/kainate antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). Co-application of CNQX plus a neurokinin-1 (NK-1) antagonist produced stronger inhibition, while co-application of CNQX, NK-1, and GRP receptor (GRPR) antagonists completely inhibited firing. Nociceptive-specific and wide dynamic range-type neurons exhibited differential suppression by CNQX plus either the GRPR or NK-1 antagonist, respectively. Neuronal responses elicited by i.d. histamine were abolished by CNQX alone. In behavioral studies, individual intrathecal administration of a GRPR, NK-1, or AMPA antagonist each significantly attenuated chloroquine-evoked scratching behavior. Co-administration of the NK-1 and AMPA antagonists was more effective, and administration of all 3 antagonists abolished scratching. Intrathecal CNQX alone prevented histamine-evoked scratching behavior. We additionally employed a double-label strategy to investigate molecular markers of pruritogen-sensitive dorsal root ganglion (DRG) cells. DRG cells responsive to histamine and/or chloroquine, identified by calcium imaging, were then processed for co-expression of SP, GRP, or vesicular glutamate transporter type 2 (VGLUT2) immunofluorescence. Subpopulations of chloroquine- and/or histamine-sensitive DRG cells were immunopositive for SP and/or GRP, with >80% immunopositive for VGLUT2. These results indicate that SP, GRP, and glutamate each partially contribute to histamine-independent itch. Histamine-evoked itch is mediated primarily by glutamate, with GRP playing a lesser role. Co-application of NK-1, GRP, and AMPA receptor antagonists may prove beneficial in treating chronic itch.

Topics: 6-Cyano-7-nitroquinoxaline-2,3-dione; Action Potentials; Animals; Antirheumatic Agents; Bombesin; Chloroquine; Drug Combinations; Excitatory Amino Acid Antagonists; Ganglia, Spinal; Gastrin-Releasing Peptide; Glutamic Acid; Male; Mice; Mice, Inbred C57BL; Neurokinin-1 Receptor Antagonists; Neurons; Peptide Fragments; Piperidines; Pruritus; Substance P; Vesicular Glutamate Transport Protein 2

Cannabinoid CB1 receptors have been shown to mediate the antinociceptive, but not the hypothermic, action of the worldwide used analgesic, paracetamol. Since itch and pain sensations share many similarities, the purpose of the present study was to investigate whether blockade of cannabinoid CB1 and CB2 receptors participates in the antipruritic activity of paracetamol in mice. Scratching behavior was induced by intradermal serotonin injection into the rostral part of the back of the mice. After serotonin administration, scratching of the injected site by the hind paws were videotaped and counted for 30 min. Serotonin-induced scratching behavior was attenuated with high-dose paracetamol (300 mg/kg). The CB1 receptor antagonist, AM-251 (1 mg/kg), and the CB2 receptor antagonist, SR-144528 (1 mg/kg), did not alter the anti-scratching behavioral effect of paracetamol. Our results indicate that, in contrast to its antinociceptive action, but similar to its hypothermic effect, cannabinoid receptors are not involved in the antipruritic activity of paracetamol.

Topics: Acetaminophen; Animals; Antipruritics; Camphanes; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Mice; Mice, Inbred BALB C; Piperidines; Pruritus; Pyrazoles; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Serotonin

Data suggest that substance P could play an important role in pruritus, and therefore, blockade of the neurokinin (NK)-1 receptor might be antipruritic. Thus, we explored in the Mongolian gerbil the effect on scratching behaviour, induced by intra-dermal injection of the NK-1 receptor-specific agonist GR73632, of oral administration of the NK-1 receptor antagonist orvepitant. Orvepitant at all doses tested (0.1-10 mg/kg p.o.) produced a profound inhibition of GR73632 (30 nmol i.d.) induced hindlimb scratching; the minimum effective dose of orvepitant in this model was identified as ≤0.1 mg/kg. The data generated supported the proposition that the antipruritic potential of orvepitant should be evaluated in clinical trials.

Topics: Administration, Oral; Animals; Antipruritics; Bridged Bicyclo Compounds, Heterocyclic; Disease Models, Animal; Dose-Response Relationship, Drug; Gerbillinae; Neurokinin-1 Receptor Antagonists; Peptide Fragments; Piperidines; Pruritus; Substance P

Previous research suggests that the acute anorectic effect of cannabinoid CB1 receptor antagonist/inverse agonists may be secondary to response competition from the compulsive scratching and grooming syndrome characteristic of these agents.. As the pruritic effect of rimonabant can be attenuated by the opioid receptor antagonist naloxone, these studies test the prediction that naloxone co-treatment should prevent acute rimonabant anorexia.. Two experiments comprehensively profiled the behavioural effects of an anorectic dose of rimonabant (1.5 mg/kg) in the absence or presence of naloxone (experiment 1: 0.01 or 0.1 mg/kg; experiment 2: 0.05 mg/kg).. In both experiments, rimonabant not only significantly suppressed food intake and time spent eating but also induced compulsive scratching and grooming. In experiment 1, although the lower dose of naloxone seemed to weakly attenuate the effects of rimonabant both on ingestive and compulsive behaviours, the higher dose more strongly suppressed the compulsive elements but did not significantly affect the anorectic response. The results of experiment 2 showed that naloxone at a dose which markedly attenuated rimonabant-induced grooming and scratching did not alter the effects of the compound on food intake or time spent feeding. The apparent independence of the ingestive and compulsive effects of rimonabant was confirmed by the observation that despite a 'normalising' effect of naloxone co-treatment on behavioural structure (BSS), the opioid antagonist did not impact the suppressant effect of rimonabant on peak feeding.. The acute anorectic response to rimonabant would not appear to be secondary to compulsive scratching and grooming.

Topics: Animals; Appetite; Behavior, Animal; Body Weight; Cannabinoid Receptor Antagonists; Compulsive Behavior; Dose-Response Relationship, Drug; Feeding Behavior; Food; Grooming; Locomotion; Male; Naloxone; Narcotic Antagonists; Piperidines; Pruritus; Pyrazoles; Rats; Rimonabant

The Skindex-16 questionnaire was recently developed as a measure of dermatological health-related quality of life (HRQoL), including symptoms, emotions and functional aspects. Bepotastine besilate is a selective histamine H(1) -receptor antagonist and a second-generation non-sedating antihistamine to treat various dermatological disorders. We assessed changes of the HRQoL instrument (Skindex-16) on patients with pruritus, including those with atopic dermatitis (AD) over bepotastine treatment period. The patients' personal assessment of the intensity of pruritus was determined using the Visual Analog Scale (VAS) for pruritus. Patients answered the Skindex-16 at baseline and at week 4. Forty-eight of 51 enrolled dermatological patients completed the Skindex-16. Of the 48 patients, 11 had AD and 37 had other conditions. Improvement in the clinical evaluation and VAS score was significant in all patients, the AD group and the other disorders group between baseline and week 4. Skindex-16 showed significantly lower scores for each of the three scales (symptoms, emotions and functioning) and the global score at baseline compared to that at week 4 in all patients and the other disorders. In contrast, there was a significant reduction in the emotions and global score among the AD patients. We found a significant correlation between falls in emotions score of Skindex-16 and falls in VAS scores for pruritus in the AD group. Bepotastine could be effective in the management of patients' HRQoL and useful in patients suffering with pruritus. We suggested that pruritus of AD patients could exert a stronger emotional effect due to the skin condition compared to the symptomatic or functional effects.

Topics: Adolescent; Adult; Aged; Dermatitis, Atopic; Emotions; Female; Histamine H1 Antagonists; Humans; Male; Middle Aged; Piperidines; Pruritus; Pyridines; Quality of Life; Surveys and Questionnaires; Young Adult

Urticaria is mainly caused by mast cell-derived histamine through the histamine H(1) receptor. Antihistamines are occasionally used on demand upon a recurrence of urticaria; therefore, rapidly acting agents should be explored. The onset of action is assumed to depend on time to maximum concentration (T(max)), but the speed of action needs to be evaluated not only through blood concentration analysis but also by measuring in vivo effectiveness.. In this study, we chose two representative second-generation antihistamines (bepotastine and fexofenadine) with relatively short T(max) values and evaluated their effects on histamine-induced skin responses using both visual and laser Doppler imaging scales.. Suppression of histamine-induced flare and itch was observed 3 and 6 h after administration of both antihistamines. Attenuation of itch was seen 30 min after the administration of each drug and thereafter until 6 h. In addition, bepotastine suppressed flare formation after only 30 min following application.. These results suggest that antihistamines suppress histamine-induced itch and flare, followed by wheal formation, and that bepotastine suppresses skin symptoms sooner after administration than fexofenadine does, which is relatively consistent with the T(max) results.

Topics: Adult; Female; Histamine; Histamine H1 Antagonists, Non-Sedating; Humans; Male; Piperidines; Pruritus; Pyridines; Skin; Terfenadine; Urticaria

Cannabinoids have recently been identified as potential neuronal modulators of pruritic response, representing a potential target in the treatment of itch associated with a variety of pathophysiologic conditions. While the selective CB(1) receptor antagonist rimonabant is an established pruritic agent in both animal and clinical testing, its receptor mechanism of action and anatomical loci remain unclear.. The purpose of this study was to determine whether CB(1) receptor blockade is critical to rimonabant-induced scratching and to identify differences in scratching response based on different routes of administration. Furthermore, experiments were designed to elucidate any evidence as to whether rimonabant elicits scratching behavior through common immunologic hypersensitivity mechanisms.. Rimonabant was equally effective at producing scratching via intraperitoneal and local subcutaneous injection. This compound also produced an intense scratching response when administered intrathecally, but had no effects after intracerebroventricular administration. Repeated administration of rimonabant led to a decreased magnitude of scratching. While rimonabant-induced scratching was not attenuated either by pretreatment with the H(1) receptor antagonist loratadine or in mast cell-deficient mice, it lacked efficacy in CB(1) (-/-) mice.. Rimonabant is a potent and fully effective pruritogen when administered spinally or systemically and requires CB(1) receptors to induce scratching, suggesting an important spinal CB(1) receptor component of action. The lack of responsiveness to H(1) antagonism or mast cell deficiency supports previous findings that cannabinoids modulate itch through neuronal mechanisms, and not by traditional hypersensitivity activation.

Topics: Animals; Behavior, Animal; Disease Models, Animal; Dose-Response Relationship, Drug; Dronabinol; Female; Histamine H1 Antagonists; Hypersensitivity; Injections, Intraperitoneal; Injections, Intraventricular; Injections, Spinal; Injections, Subcutaneous; Loratadine; Male; Mast Cells; Mice; Mice, Inbred C57BL; Mice, Knockout; Pain; Piperidines; Pruritus; Pyrazoles; Receptor, Cannabinoid, CB1; Rimonabant

Remifentanil patient-controlled analgesia (PCA) was introduced to a small maternity unit where an extensive epidural service was difficult to provide. This was a new service and the New Zealand College of Midwives had serious doubts about the efficacy and safety of remifentanil, so auditing its use was important. In a two-stage audit, clinical notes of 244 consecutive remifentanil users were studied between January 2008 and November 2009. We developed a questionnaire to assess the parturients' satisfaction with remifentanil PCA and designed a proforma to evaluate it against four standards of best practice. During the two audit periods, timely commencement of PCA was achieved in 65% and 82% of cases, respectively. A 70% compliance rate with monitoring standards fell to 10% after the withdrawal of supervision by an acute pain team, but improved to 91% following implementation of regular midwifery training sessions and a redesigned partogram and prescription flowchart. Ninety-four percent of women rated remifentanil PCA as excellent, very good or good. Maternal side-effects were nausea, pruritus and drowsiness. A comparison of Apgar scores of consecutive neonates born by normal vaginal delivery to women receiving no analgesia, with those born to women using remifentanil PCA, demonstrated no difference. As a result of our audit, remifentanil PCA is now viewed by our midwives as an effective and safe method when accompanied by 1:1 care and appropriate monitoring. With our input other maternity units have introduced it, especially where epidural service provision is limited, and for patients in whom epidural analgesia is contraindicated.

Topics: Adult; Analgesia, Obstetrical; Analgesia, Patient-Controlled; Anesthetics, Intravenous; Apgar Score; Female; Fetus; Guideline Adherence; Humans; Medical Audit; Midwifery; Monitoring, Intraoperative; Monitoring, Physiologic; New Zealand; Patient Satisfaction; Piperidines; Postoperative Nausea and Vomiting; Pregnancy; Pruritus; Remifentanil; Surveys and Questionnaires

There is an on-going need to identify medications suitable for the long-term treatment of canine atopic dermatitis (CAD). Masitinib mesilate is a potent and selective tyrosine kinase inhibitor of the c-KIT receptor. A strong relationship exists between the SCF/c-KIT pathway and pathogenesis of CAD, suggesting that masitinib may potentially fulfil the above role. This study reports on an uncontrolled pilot study of masitinib in CAD. Masitinib was administered orally to 11 dogs at a mean dose of 11.0 +/- 1.83 mg/kg/day (free base) for 28 days. Treatment response was assessed by evolution of clinical appearance according to a modified version of the Canine Atopic Dermatitis Extent and Severity Index (mCADESI), pruritus scale and surface area of lesions. Masitinib improved CAD with a mean reduction in mCADESI of 50.7 +/- 29.8% (95% C.I. = 29.4-72.0; p = 0.0004) at day 28 relative to baseline, with 8/10, 8/10 and 4/10 dogs showing improvement of >or=33%, >or=40% and >or=50%, respectively. Improvement was further evidenced by a decrease in pruritus score and the surface area of lesions. No serious or severe adverse events occurred during this trial, although 6/11 dogs presented with mild to moderate treatment related adverse events. There is sufficient compelling evidence to warrant further investigation.

Topics: Animals; Benzamides; Dermatitis, Atopic; Dog Diseases; Dogs; Drug-Related Side Effects and Adverse Reactions; Pilot Projects; Piperidines; Pruritus; Pyridines; Severity of Illness Index; Skin; Thiazoles; Treatment Outcome

To examine the antinociceptive effects of N-Methyl-D-aspartate (NMDA) receptor NR2 subunit antagonists in a rat model of the facial formalin test.. Experiments were carried out on adult male Sprague-Dawley rats weighing 220 to 280 g. Anesthetized rats were individually mounted on a stereotaxic frame and a polyethylene tube was implanted for intracisternal injection and, 72 hours later, formalin tests were performed. NMDA receptor antagonists were administered intracisternally 10 minutes prior to subcutaneous injection of 5% formalin (50 MicroL) into the vibrissal pad.. The intracisternal administration of 25, 50, or 100 Microg of memantine, an antagonist that acts at the NMDA ion channel site, significantly suppressed the number of scratches in the second phase of the behavioral responses to formalin. Intracisternal administration of a range of doses of 5,7-dichlorokynurenic acid, a glycine site antagonist, or DL-2-amino-5-phosphonopentanoate (AP-5), a nonselective NMDA site antagonist, produced significant antinociceptive effects in the second phase. Intracisternal administration of 1, 2.5, or 5 Microg of (2R,4S)-4-(3 Phosphonopropyl)-2-piperidine_carboxylic acid (PPPA), a competitive NR2A antagonist, significantly suppressed the number of scratches in the second phase, while only the highest dose of PPPA (5 Microg) significantly suppressed the number of scratches in the first phase. The antinociceptive effects of intracisternal injection of (alphaR, betaS)-alpha-(4Hydroxyphenyl)-_ methyl-4-(phenylmethyl)-1-Piperidinepropanol maleate(Ro 25-6981), a selective NR2B antagonist, were similar to those of PPPA. Injection of memantine, AP-5, Ro 25-6981, or vehicle did not result in any motor dysfunction. A low dose of PPPA (1 microg) or 5,7-dichlorokynurenic acid (2.5 microg) did not affect motor function. However, higher doses of PPPA and 5,7-dichlorokynurenic acid produced motor dysfunction.. The present results suggest that central NR2 subunits play an important role in orofacial nociceptive transmission. Moreover, this data also indicate that targeted inhibition of the NMDA receptor NR2 subunit is a potentially important new treatment approach for inflammatory pain originating in the orofacial area.

Topics: Animals; Behavior, Animal; Cisterna Magna; Disease Models, Animal; Excitatory Amino Acid Antagonists; Facial Pain; Formaldehyde; Injections; Injections, Subcutaneous; Kynurenic Acid; Male; Memantine; Motor Activity; Nociceptors; Phenols; Piperazines; Piperidines; Pruritus; Rats; Rats, Sprague-Dawley; Receptors, N-Methyl-D-Aspartate; Synaptic Transmission; Time Factors; Vibrissae

Six allergic conjunctivitis patients (12 eyes) and 4 healthy volunteers (8 eyes) were investigated in terms of the effect of cooling sheets on eye itching and tear histamine concentration, before and 5 min after cooling the eyelids with cooling sheets. The severity of itching was evaluated with a five-level itching score. The combination treatment of levocabastine with cooling sheets significantly reduced eye itching, while no significant change in tear histamine concentration was observed before and after cooling sheet use. The cooling sheets are useful for reducing eye itching in the therapy of allergic conjunctivitis. The tear histamine concentration did not correlate with the antiitching effect of cooling sheets in this study.

Topics: Conjunctivitis, Allergic; Cryotherapy; Enzyme-Linked Immunosorbent Assay; Histamine; Histamine H1 Antagonists, Non-Sedating; Humans; Ophthalmic Solutions; Piperidines; Pruritus; Severity of Illness Index; Tears

Endothelin-1 (ET-1) has recently been identified to evoke pruritus/itching sensation in both humans and animals. It is most likely that the signaling is through the specific G-protein-coupled ET(A) and ET(B) receptors, but the downstream signaling mediators for ET-1 remain elusive. In the present study, we examined the potential involvement of several distinct signaling molecules in ET-1-induced pruritus in a murine model. We applied an in vivo pruritus model in C57BL/6J mice by injecting ET-1 intradermally into the scruff, and recording the number of scratching bouts within 30 min after injection. Then specific antagonists/inhibitors for distinct signaling molecules, including cell-surface ET(A) and ET(B) receptors, histamine receptor type 1 (H1 receptor), protein kinases A (PKA) and C (PKC), phospholipase C (PLC) or adenylyl cyclase (AC), were co-injected with ET-1. The results showed that ET-1 induced a vigorous scratching response in mice in a dose-dependent manner. This response was further enhanced by a specific antagonist for ET(B) receptor, BQ-788, reduced by a specific antagonist for ET(A) receptor, BQ-123, and not affected by mepyramine, the specific inhibitor for H1 receptor. In addition, the scratching response was significantly reduced by inhibitors for PKC and AC, but was significantly enhanced by PLC inhibitor, while PKA inhibitors showed no effects in the ET-1-induced scratching response. Our data suggested that ET-1 may signal through the ET(A) receptor, AC and PKC pathway to induce pruritus sensation, while ET(B) receptor and PLC may antagonize the pruritus evoked by ET-1. These results may provide a basis for the future development of antipruritic therapy.

Topics: Adenylyl Cyclase Inhibitors; Adenylyl Cyclases; Animals; Cyclic AMP-Dependent Protein Kinases; Endothelin A Receptor Antagonists; Endothelin B Receptor Antagonists; Endothelin-1; Histamine Antagonists; Mice; Mice, Inbred C57BL; Oligopeptides; Peptides, Cyclic; Piperidines; Protein Kinase C; Pruritus; Pyrilamine; Receptor, Endothelin A; Receptor, Endothelin B; Receptors, Histamine H1; Signal Transduction; Type C Phospholipases

Behavioral effects of a nonpeptidic NOP (nociceptin/orphanin FQ Peptide) receptor agonist, Ro 64-6198, have not been studied in primate species. The aim of the study was to verify the receptor mechanism underlying the behavioral effects of Ro 64-6198 and to systematically compare behavioral effects of Ro 64-6198 with those of a mu-opioid receptor agonist, alfentanil, in monkeys. Both Ro 64-6198 (0.001-0.06 mg/kg, s.c.) and alfentanil (0.001-0.06 mg/kg, s.c.) produced antinociception against an acute noxious stimulus (50 degrees C water) and capsaicin-induced allodynia. An NOP receptor antagonist, J-113397 (0.01-0.1 mg/kg, s.c.), dose-dependently produced rightward shifts of the dose-response curve of Ro 64-6198-induced antinociception. The apparent pA(2) value of J-113397 was 8.0. Antagonist studies using J-113397 and naltrexone revealed that Ro 64-6198 produced NOP receptor-mediated antinociception independent of mu-opioid receptors. In addition, alfentanil dose-dependently produced respiratory depression and itch/scratching responses, but antinociceptive doses of Ro 64-6198 did not produce such effects. More important, Ro 64-6198 did not produce reinforcing effects comparable with those of alfentanil, cocaine, or methohexital under self-administration procedures in monkeys. These results provide the first functional evidence that the activation of NOP receptors produces antinociception without reinforcing effects in primates. Non-peptidic NOP receptor agonists may have therapeutic value as novel analgesics without abuse liability in humans.

Topics: Alfentanil; Analgesics, Opioid; Animals; Behavior, Animal; Benzimidazoles; Capsaicin; Central Nervous System Agents; Dose-Response Relationship, Drug; Female; Hot Temperature; Imidazoles; Macaca mulatta; Male; Naltrexone; Narcotic Antagonists; Nociceptin Receptor; Pain; Piperidines; Pruritus; Receptors, Opioid; Receptors, Opioid, mu; Reinforcement, Psychology; Respiratory Insufficiency; Spiro Compounds

The cannabinoid CB1 selective antagonist SR141716A (Rimonabant) has been shown to decrease body weight in laboratory animals and humans. Furthermore, SR141716A can elicit scratching behavior in rodents, a behavior that has been hypothesized to contribute to SR141716A-induced decrease in food intake. Although childhood obesity is a rising health issue, it is unknown whether SR141716A is equipotent at modulating food intake and other CB1-mediated behaviors in younger subjects.. To determine whether CB1 receptor blockade is equipotent at modulating food and water intake, body weight, and scratching behavior, the effect of a range of SR141716A doses on these behaviors in food-restricted postnatal day (P) 18, 28, and 60 male rats was investigated. Brain concentrations of SR141716A were determined in each age group.. SR141716A dose- and age-dependently suppressed food and water intake and body weight gain and elicited head scratching, with the most potent effects observed in P18 and P28 rats. Brain concentrations of SR141716A were significantly elevated in P18 rats relative to P28 and P60 rats. SR141716A-elicited head scratching was attenuated by the 5-HT(2A/2C) antagonist ketanserin.. SR141716A is more potent at modulating food intake and head scratching in very young animals; these differences can be attributed to an increase in brain penetration of SR141716A for P18 but not for P28 and P60 rats. In addition, SR141716-elicited head scratching is modulated by 5HT receptor antagonism and is not a contributing factor to SR141716A's anorectic effects.

Topics: Age Factors; Animals; Brain; Dose-Response Relationship, Drug; Drinking; Eating; Feeding Behavior; Ketanserin; Male; Piperidines; Pruritus; Pyrazoles; Rats; Rats, Sprague-Dawley; Receptor, Cannabinoid, CB1; Rimonabant; Serotonin Antagonists; Weight Gain

Pruritus is the most severe problem in atopic dermatitis. Even though its mechanism is still not fully understood, antihistamines have been prescribed for atopic dermatitis.. To evaluate the effect of antihistamine on atopic dermatitis, we analyzed the scratching behavior in atopic dermatitis model NC/Nga mice.. BALB/c mice, in which scratching behavior was induced by intradermal injection of compound 48/80 (100 microg/100 microl/mouse), and NC/Nga mice, housed in a conventional environment and having developed spontaneous eczematous regions, were monitored with a SCLABA system after oral administration of bepotastine besilate. The number of eosinophils in the ear skin and the serum leukotriene B(4) (LTB(4)) levels were also evaluated.. Bepotastine at doses of 3 and 10 mg/kg effectively inhibited the compound 48/80-induced scratching behavior of BALB/c mice 1 h after oral administration, comparable with the blood T(max), which was reached within 0.8-1.6 h in humans. Bepotastine also significantly inhibited the scratching behavior of NC/Nga mice 1 h after oral administration. Even though 10 mg/kg bepotastine could not influence the number of tissue eosinophils, it effectively suppressed the serum LTB(4) levels, just comparable with the suppression of scratch behavior of NC/Nga mice.. Bepotastin effectively suppressed the scratch behavior of atopic dermatitis model mice, which may not simply be explained by the suppression of histamine but also by the suppression of other mediators like LTB(4). Bepotastine could be useful in the treatment of pruritus, especially early after oral administration.

Topics: Administration, Oral; Animals; Antipruritics; Behavior, Animal; Dermatitis, Atopic; Disease Models, Animal; Male; Mice; Mice, Inbred BALB C; Mice, Inbred Strains; p-Methoxy-N-methylphenethylamine; Piperidines; Pruritus; Pyridines

We examined the therapeutic potential of a proprietary Croton palanostigma extract (Zangrado(R)) in the management of emesis and itch.. Emesis was induced in ferrets with morphine-6-glucuronide (0.05 mg/kg sc) in the presence of Zangrado (3 mg/kg, ip) and the cannabinoid receptor 1 antagonist, AM 251 (5 mg/kg, ip). Topical Zangrado (1%) was assessed for anti-pruretic actions in the 5-HT-induced scratching model in rats and evaluated in capsaicin-induced gastric hyperemia as measured by laser doppler flow. In the ApcMinmouse model of precancerous adenomatosis polyposis, mice received Zangrado (100 mug/ml in drinking water) from the age of 6 - 16 weeks for effects on polyp number. In RAW 264.7 cells Zangrado was examined for effects on lipopolysaccharide-induced nitrite production.. Zangrado was a highly effective anti-emetic, reducing morphine-induced vomiting and retching by 77%. These benefits were not associated with sedation or hypothermia and were not reversed by cannabinoid receptor antagonism. Itch responses were blocked in both the morphine and 5-HT models. Zangrado did not exacerbate the ApcMincondition rather health was improved. Capsaicin-induced hyperemia was blocked by Zangrado, which also attenuated the production of nitric oxide by activated macrophages.. Zangrado is an effective anti-emetic and anti-itch therapy that is devoid of common side-effects, cannabinoid-independent and broadly suppresses sensory afferent nerve activation. This complementary medicine represents a promising new approach to the management of nausea, itch and irritable bowel syndrome.

Topics: Animals; Antiemetics; Antipruritics; Cell Line; Croton; Ferrets; Male; Mice; Mice, Inbred C57BL; Morphine Derivatives; Nausea; Piperidines; Plant Extracts; Proanthocyanidins; Pruritus; Pyrazoles; Rats; Rats, Sprague-Dawley; Receptor, Cannabinoid, CB1; Vomiting

Endothelin-1 (ET-1) is present in murine and human skin and causes itch (pruritus) when injected in humans. This behavioural study examined the scratch reflex evoked by ET-1 in mice.. An automated detector was used to determine whether ET-1 causes reflex scratching, the behavioural correlate of itching, in BALB/c mice. Selective agonists and antagonists were used to probe the ET receptor(s) involved.. ET-1 evoked dose-related reflex scratching lasting up to 20 min following intradermal injection (0.1-100 ng; 0.04-40 pmol). The ED(50) for ET-1 induced scratching was 2.1 ng and desensitization occurred with cumulative dosing. High doses of the ET(B) receptor agonist IRL1620 (10 microg; 5.5 nmol), also caused scratching (ED(50) 1.3 microg, 0.7 nmol). The ET(A) receptor antagonist BQ123 significantly reduced scratching evoked by ET-1 and IRL 1620, suggesting that both agonists caused scratching via an ET(A) receptor-dependent mechanism. The ET(B) receptor antagonist BQ788 significantly reduced scratching evoked by IRL1620 but had no effect on scratching evoked by ET-1. This indicated that activation of ET(B) receptors by high doses of ET(B) agonist, but not ET-1, can trigger scratching.. ET-1 is a potent endogenous activator of reflex scratching (itch). Mechanisms for ET-induced scratching are considered, including direct action of ET-1 on pruriceptive nerve endings and indirect actions via release of endogenous mediators such as histamine from mast cells. ET-1 and ET(A) receptors, possibly also ET(B) receptors, are potential targets for developing specific anti-pruritic drugs to treat pruritic skin disorders such as atopic dermatitis.

Topics: Animals; Behavior, Animal; Dose-Response Relationship, Drug; Endothelin A Receptor Antagonists; Endothelin B Receptor Antagonists; Endothelin-1; Endothelins; Female; Injections, Intradermal; Mice; Mice, Inbred BALB C; Oligopeptides; Peptide Fragments; Peptides, Cyclic; Piperidines; Pruritus; Receptor, Endothelin A; Receptor, Endothelin B; Reflex

Although the CB1 receptor antagonist/inverse agonist rimonabant acutely suppresses food intake in rodents, the behavioural specificity of this effect remains unclear.. To profile the behavioural effects of rimonabant in a free-feeding context.. Videoanalysis was employed to characterise the effects of acute rimonabant (1.5 and 3.0 mg/kg, IP) on the behaviour of non-deprived male rats exposed to palatable mash. Data were also collected on post-treatment weight gain, and, as prolonged appetite suppression has been found after single dosing with compounds of this series, rats were reassessed (drug-free) for food intake 7 days after initial testing.. Both doses of rimonabant not only decreased mash consumption (44-55%) but also reduced 24-h weight gain. Although videoanalysis confirmed the inhibitory effects of rimonabant on feeding behaviour, it also revealed concurrent reductions in locomotion, rearing and sniffing as well as substantial (up to tenfold) and dose-dependent increases in grooming and scratching. Timecourse analyses further revealed that rimonabant dose-dependently induced frequent episodes of atypical scratching that waned over the test but which were succeeded by prolonged and behaviourally disruptive grooming. Finally, as groups did not differ in mash consumption on retest, any prolonged anorectic effect of acute rimonabant dissipates within 7 days of treatment.. The anorectic response to rimonabant in male rats would appear to be due largely to response competition. This parsimonious conclusion is supported by the less profound (although still significant) increases in scratching and grooming observed in rats treated with a sub-anorectic dose (0.5 mg/kg) of the compound.

Topics: Animals; Anorexia; Data Interpretation, Statistical; Dose-Response Relationship, Drug; Eating; Feeding Behavior; Grooming; Habituation, Psychophysiologic; Injections, Intraperitoneal; Male; Piperidines; Pruritus; Pyrazoles; Rats; Receptor, Cannabinoid, CB1; Rest; Rimonabant; Satiety Response; Time Factors; Videotape Recording; Weight Gain

Anti-pruritic effects of the antihistamine bepotastine besilate were studied in mice. Bepotastine besilate (10 mg/kg) inhibited scratching induced by an intradermal injection of histamine (100 nmol/site), but not serotonin (100 nmol/site). Bepotastine besilate (1-10 mg/kg, oral) dose-dependently suppressed scratching induced by substance P (100 nmol/site) and leukotriene B(4) (0.03 nmol/site). An intradermal injection of substance P (100 nmol/site) increased the cutaneous concentration of leukotriene B(4), which was not affected by bepotastine besilate (10 mg/kg, oral). Leukotriene B(4) increased Ca(2+) concentration in cultured neutrophils, which was suppressed by bepotastine besilate (1-100 microM). Leukotriene B(4) increased Ca(2+) concentration in cultured dorsal root ganglion neurons, which was also suppressed by bepotastine besilate (100 microM). The results suggest that the inhibition of the actions of leukotriene B(4) as well as histamine is involved in the anti-pruritic effect of bepotastine besilate.

Topics: Administration, Oral; Animals; Behavior, Animal; Calcium; Dose-Response Relationship, Drug; Ganglia, Spinal; Histamine H1 Antagonists; Leukotriene B4; Male; Mice; Mice, Inbred ICR; Neurons; Neutrophils; Piperidines; Pruritus; Pyridines; Skin; Substance P

Pain and itch sensations are induced by depolarization of C-fibre nerves and possibly other types of fibres. We have evidence from several species, including mice, that skin plasma extravasation induced by the Phoneutria nigriventer spider venom (PNV) is dependent on tachykinin NK(1) receptors. We have now investigated the itching measured as bouts of scratching in response to intradermal (i.d.) PNV in wildtype (NK(1)(+/+)) and NK(1) receptor knockout (NK(1)(-/-)) mice. Mice, either NK(1)(+/+) or NK(1)(-/-), were given a single i.d. injection (0.05 ml) of test agent or vehicle into the shaved dorsal skin, in the intercostal region, in a randomized way. The bouts of scratching were recorded in a blinded manner for 60 min. Oedema formation was concomitantly assessed by the extravascular accumulation of i.v. injected (125)I-albumin. The i.d. injection of either substance P (at a high dose of 100 nmol/site), or PNV (0.3-10 microg/site) induced oedema formation in NK(1)(+/+) but substantially less was observed in NK(1)(-/-) mice, as previously reported. PNV also induced scratching, but significantly less scratching was observed in NK(1)(-/-) compared with NK(1)(+/+) mice. In contrast, SP did not induce significant scratching at amounts up to 100 nmol in NK(1)(+/+) mice. Experiments with an NK(1) receptor antagonist SR140333 (at doses that blocked PNV-induced oedema) revealed that whilst a local co-injection i.d. (1 nmol) in NK(1)(+/+) mice had no effect on PNV (3 microg/site)-induced scratching (18.5+/-3.7 vs. 14.4+/-3.5 bouts, mean+/-S.E.M., n=5-7), systemic treatment with SR140333 (120 nmol/kg, i.v.) significantly inhibited scratching (14+/-3.5 vs. 3.1+/-1.2 bouts, n=4-6; P<0.05). These results indicate that NK(1) receptors are involved in mediating PNV-induced scratching and that the location of the receptors is unlikely to be skin. Thus, a distinct separation between endogenous microvascular and PNV nociceptive NK(1)-dependent effects is suggested.

Topics: Administration, Topical; Animals; Dose-Response Relationship, Drug; Edema; Female; Injections, Intradermal; Injections, Intravenous; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Neurokinin-1 Receptor Antagonists; Piperidines; Pruritus; Quinuclidines; Receptors, Neurokinin-1; Skin; Spider Venoms; Substance P; Vasculitis, Leukocytoclastic, Cutaneous

Histamine is one of the most common chemical mediators causing pruritus, and H1 receptor antagonists have been used as a first choice in its treatment. On the other hand, although the presence of H3 receptors has been identified in the skin, few studies have investigated the involvement of H3 receptors on pruritus.. The purpose of this study was to examine whether H3 receptor agonist or antagonist influences the incidence of scratching behaviour in ICR or mast cell-deficient WBB6F1-W/WV mice.. The mice were given an intradermal injection of H3 receptor agonist or antagonist into the rostral part of the back, and the occurrence of scratching behaviour at the injected site by the hind paws was counted over 60 min.. H3 receptor antagonists, thioperamide and AQ0145 significantly increased the incidence of scratching behaviour in ICR mice. H3 receptor agonist, (R)-alpha-methylhistamine, had no effect. On the other hand, (R)-alpha-methylhistamine significantly inhibited thioperamide or AQ0145-induced scratching behaviour. In addition, both thioperamide and AQ0145 elicited scratching behaviour in mast cell-deficient WBB6F1-W/WV mice.. From these results, it may be concluded that H3 receptors are involved in the modulation of pruritus in the skin, and mast cells are not essential in this response. In addition, H3 receptor agonists can be useful as a novel therapeutic approach against pruritus.

Topics: Adamantane; Amidines; Animals; Female; Histamine Agonists; Histamine H2 Antagonists; Imidazoles; Mast Cells; Methylhistamines; Mice; Mice, Inbred ICR; Mice, Mutant Strains; Piperidines; Pruritus; Receptors, Histamine H3; Skin

Large doses (10-40 mg/kg) of the selective cannabinoid CB(1) receptor antagonist, SR 141716A, produce the head-twitch response (HTR) and scratching in rodents and vomiting in the least shrew (Cryptotis parva). Agents that increase brain serotonin (5-HT) levels induce the HTR in rodents, whereas enhancements in either brain 5-HT or dopamine concentrations can lead to production of emesis in vomiting species. The present study was undertaken to demonstrate whether large doses of SR 141716A can (1) induce the HTR and scratching in the least shrew and (2) cause concurrent biochemical changes in brain 5-HT and dopamine concentrations. SR 141716A (0, 1, 5, 10, 20 and 40 mg/kg i.p.) administration induced the HTR, scratching and vomiting. The HTR effect was bell shaped with a maximum frequency occurring at the 20 mg/kg SR 141716A dose, whereas the scratching and vomiting behaviors displayed dose-dependent effects. The selective 5-HT(2A/C) receptor antagonist, SR 46349B (0, 0.1, 0.25, 1, 3 and 6 mg/kg i.p.), differentially attenuated all SR 141716A (20 mg/kg)-induced behaviors because the HTR was relatively more potently and completely blocked. In the shrew forebrain, SR 141716A (20 and 40 mg/kg ip) caused dose- and time-dependent increases in the levels of 5-HT and dopamine and the concentrations of their major metabolites [5-hydroxyindole acetic acid (5-HIAA), 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanilic acid (HVA)] and the turnover of both monoamines. Although the effects of SR 141716A on brainstem concentrations of both monoamines and their metabolites were not always consistent, the CB(1) antagonist did increase the turnover of both 5-HT and dopamine. The present findings suggest that the mechanism and the neurochemical substrate for SR 141716A-induced HTR and scratching behaviors is enhancement of 5-HT release, whereas increased release of 5-HT and dopamine probably contributes to the production of emesis.

Topics: Animals; Behavior, Animal; Brain; Dopamine; Dose-Response Relationship, Drug; Female; Male; Piperidines; Pruritus; Pyrazoles; Receptor, Cannabinoid, CB1; Rimonabant; Serotonin; Shrews; Vomiting

Topics: Analgesics, Opioid; Antipruritics; Humans; Nalbuphine; Pain, Postoperative; Piperidines; Pruritus; Remifentanil

Topics: Adult; Female; Humans; Male; Nitriles; Phenothiazines; Piperidines; Pruritus; Pruritus Ani; Pruritus Vulvae; Psychophysiologic Disorders; Tranquilizing Agents

Topics: Anti-Allergic Agents; Dermatitis, Atopic; Eczema; Histamine H1 Antagonists; Humans; Hypersensitivity; Piperidines; Pruritus; Skin Diseases; Tartrates

Topics: Central Nervous System Stimulants; Piperidines; Pruritus; Skin Diseases; Tripelennamine

Topics: Histamine H1 Antagonists; Humans; Piperidines; Pruritus

Topics: Humans; Piperidines; Pruritus; Skin