olopatadine-hydrochloride and levocetirizine

The antihistamine effects of olopatadine and levocetirizine, in standard-dose application described in their information (5 mg twice a day for olopatadine; 5 mg once daily for levocetirizine), were examined from 11.5 to 24 h after application. The test was designed in a double-blind, randomized, cross-over, placebo-controlled study of 12 healthy volunteers on histamine-induced flare and wheal response using an iontophoresis technique. The suppressive effect of olopatadine on the wheals induced by a 0.1-mA histamine iontophoresis lasted for 24 h after dosing. Both drugs inhibited flare induced by histamine iontophoresis almost completely until 24 h after the first administration. Suppression of the 0.2-mA-induced wheal response by levocetirizine, taken once daily, decreased with time, although 0.1-mA-induced flare was almost completely suppressed by the drug. Olopatadine completely suppressed even the wheal response induced by a 0.2-mA histamine iontophoresis. Compared with the placebo, the two drugs significantly suppressed the subjective itching assessed by visual analog scale at all intervals. There were no significant differences in subjective drowsiness and objective cognitive function between drug- and placebo-treated subjects. These results demonstrate that olopatadine seems to be more potent than levocetirizine when administrated in a standard dose. In conclusion, mild to moderate urticaria could be controlled by standard application as described in their information. On the other hand, severe urticaria could be managed by a standard application of olopatadine, but levocetirizine may need an additional dose to control severe urticaria.

Topics: Adult; Cetirizine; Cognition; Cross-Over Studies; Dibenzoxepins; Double-Blind Method; Female; Healthy Volunteers; Histamine; Histamine H1 Antagonists, Non-Sedating; Humans; Iontophoresis; Male; Middle Aged; Olopatadine Hydrochloride; Pruritus; Sleep Stages; Young Adult

Chronic urticaria (CU) is characterized by frequent appearance of wheals for ≥ 6 weeks. This study was undertaken to compare effectiveness and safety of olopatadine, a newer antihistamine with additional anti-inflammatory properties, in treating CU in comparison to the established second-generation antihistamine levocetirizine.. A single center, assessor-blind, randomized (1:1), active-controlled, parallel group, Phase IV trial (CTRI/2011/08/001965) was conducted with 120 adult CU patients of either sex. Subjects received either olopatadine (5 mg b.i.d.) or levocetirizine (5 mg/day) for 9 weeks, continuously for first 4 weeks and then on demand basis for last 5 weeks. Primary outcome measures were urticaria activity score (UAS) and urticaria total severity score (TSS). Routine hematological and biochemical tests and treatment-emergent adverse events were monitored for safety.. Data from 54 subjects on olopatadine and 51 on levocetirizine were analyzed for effectiveness. UAS and TSS values declined significantly with both drugs over the treatment period but the reduction was greater with olopatadine. Adverse event profiles were comparable with sedation being the commonest complaint.. Olopatadine is a safe and more effective alternative to levocetirizine in the treatment of CU.

Topics: Administration, Oral; Adult; Aged; Aged, 80 and over; Anti-Allergic Agents; Cetirizine; Chronic Disease; Dibenzoxepins; Double-Blind Method; Female; Histamine H1 Antagonists; Histamine H1 Antagonists, Non-Sedating; Humans; Male; Middle Aged; Olopatadine Hydrochloride; Single-Blind Method; Urticaria; Young Adult

Drug-target binding kinetics are suggested to be important parameters for the prediction of in vivo drug-efficacy. For G protein-coupled receptors (GPCRs), the binding kinetics of ligands are typically determined using association binding experiments in competition with radiolabelled probes, followed by analysis with the widely used competitive binding kinetics theory developed by Motulsky and Mahan. Despite this, the influence of the radioligand binding kinetics on the kinetic parameters derived for the ligands tested is often overlooked. To address this, binding rate constants for a series of histamine H

Topics: Binding, Competitive; Cetirizine; Datasets as Topic; Fluorescence Resonance Energy Transfer; Fluorescent Dyes; HEK293 Cells; Histamine H1 Antagonists; Humans; Ligands; Molecular Probes; Olopatadine Hydrochloride; Protein Binding; Pyrilamine; Radioligand Assay; Receptors, Histamine H1; Tritium

Antihistamines are widely used to treat allergy symptoms. First-generation antihistamines have adverse effects on the central nervous system (CNS), such as hypnotic and amnesic effects, whereas second-generation antihistamines have poor brain penetration, and therefore, have fewer CNS-related adverse effects. Memory consists of several phases, including acquisition, consolidation, expression, and extinction. It remains unclear whether these phases are affected by antihistamines. We investigated the effects of diphenhydramine, a first-generation antihistamine, and levocetirizine and olopatadine, second-generation antihistamines, on memory phases. Mice were subjected to fear conditioning on day 1 and tested on day 2. Antihistamines were administered before conditioning, immediately after conditioning, or before the test session. Diphenhydramine (30mg/kg) decreased freezing time when administered immediately after conditioning or before the test session. These effects were not attributable to a change in locomotor activity. Levocetirizine (0.1, 1, 10mg/kg) and olopatadine (1, 10, 20mg/kg) had no effects on conditioned fear. We also examined the effect of diphenhydramine and levocetirizine on the expression of an activity-dependent gene associated with the test session. Diphenhydramine, but not levocetirizine, increased Arc transcription in the central nucleus of the amygdala. These data indicate that diphenhydramine, but not levocetirizine or olopatadine, impairs the consolidation and expression of conditioned fear.

Topics: Amygdala; Animals; Behavior, Animal; Cetirizine; Conditioning, Psychological; Dibenzoxepins; Diphenhydramine; Electroshock; Extinction, Psychological; Fear; Freezing Reaction, Cataleptic; Histamine Antagonists; Histamine H1 Antagonists; Histamine H1 Antagonists, Non-Sedating; Male; Memory; Mice; Mice, Inbred C57BL; Olopatadine Hydrochloride