minocycline and Back-Pain

Less than 50% of patients experience sufficient pain relief with current drug therapy for neuropathic pain. Minocycline shows promising results in rodent models of neuropathic pain but was not studied in humans with regard to the treatment of neuropathic pain.. In this randomized, double-blind, placebo-controlled clinical trial, patients with subacute lumbar radicular pain received placebo, amitriptyline 25 mg, or minocycline 100 mg once a day (n = 20 per group) for 14 days. Primary outcome measure was the pain intensity in the leg as measured by a numeric rating scale ranging from 0 to 10 on days 7 and 14. Secondary outcome measures were the reduction of neuropathic pain symptoms in the leg as determined with a neuropathic pain questionnaire, consumption of rescue medication, and adverse events on days 7 and 14.. Sixty patients were randomized and included in an intention-to-treat analysis. After 14 days, patients in the minocycline and amitriptyline groups reported a reduction of 1.47 (95% confidence interval, 0.16-2.83; P = 0.035) and 1.41 (95% confidence interval, 0.05-2.78; P = 0.043), respectively, in the numeric rating scale compared to the placebo group. No differences were seen in the neuropathic pain questionnaire values at any time point during treatment between the three groups. The rate of adverse events in the amitriptyline group was 10% versus none in the minocycline and placebo groups. No differences were noted in the consumption of rescue medication.. Although both groups differed from placebo, their effect size was small and therefore not likely to be clinically meaningful.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Amitriptyline; Analgesics, Non-Narcotic; Back Pain; Brain-Derived Neurotrophic Factor; Double-Blind Method; Female; Humans; Male; Middle Aged; Minocycline; Neuralgia; Pain Measurement; Spinal Nerve Roots; Treatment Outcome; Young Adult

We characterized pain behavior and cutaneous blood flow response induced by activation of the spinal transient receptor potential ankyrin 1 (TRPA1) channel using intrathecal drug administrations in the rat. Additionally, we assessed whether the pronociceptive actions induced by intrathecally administered dynorphin A, cholecystokinin or prostaglandin F(2α) are mediated by the spinal TRPA1 channel. Cinnamaldehyde, a TRPA1 agonist, produced a dose-related (3-10 μg) cutaneous blood flow increase and mechanical hypersensitivity effect. These effects at the currently used doses were of short duration and attenuated, although not completely, by pretreatment with A-967079, a TRPA1 antagonist. The cinnamaldehyde-induced hypersensitivity was also reduced by pretreatment with minocycline (an inhibitor of microglial activation), but not by carbenoxolone (a gap junction decoupler). In vitro study, however, indicated that minocycline only poorly blocks the TRPA1 channel. The mechanical hypersensitivity effect induced by dynorphin A, but not that by cholecystokinin or prostaglandin F(2α), was attenuated by a TRPA1 antagonist Chembridge-5861528 as well as A-967079. The cinnamaldehyde-induced cutaneous blood flow increase was not suppressed by MK-801, an NMDA receptor antagonist, or bicuculline, a GABA(A) receptor antagonist. The results indicate that spinal TRPA1 channels promote mechanical pain hypersensitivity and due to antidromic activation of nociceptive nerve fibers increase cutaneous blood flow. The attenuation of the cinnamaldehyde-induced hypersensitivity effect by minocycline may be explained by action other than block of the TRPA1 channel. Moreover, the spinal TRPA1 channel is involved in mediating the pronociceptive action of dynorphin A, but not that of the spinal cholecystokinin or prostaglandin F(2α).

Topics: Acrolein; Analgesics, Non-Narcotic; Animals; Back Pain; Behavior, Animal; Cholecystokinin; Dinoprost; Dose-Response Relationship, Drug; Dynorphins; Hyperalgesia; Injections, Spinal; Male; Minocycline; Nerve Tissue Proteins; Oximes; Physical Stimulation; Posterior Horn Cells; Rats; Rats, Wistar; Regional Blood Flow; Skin; TRPA1 Cation Channel; TRPC Cation Channels

Topics: Abdominal Pain; Adolescent; Anti-Bacterial Agents; Back Pain; Diagnosis, Differential; Diplopia; Emergency Nursing; Female; Humans; Medical History Taking; Minocycline; Nausea; Nursing Assessment; Physical Examination; Pseudotumor Cerebri

Topics: Anti-Bacterial Agents; Back Pain; Ceftazidime; Cephalosporins; Discitis; Female; Humans; Lumbar Vertebrae; Magnetic Resonance Imaging; Middle Aged; Minocycline; Renal Dialysis; Ultrasonography

Topics: Acupuncture Therapy; Aged; Back Pain; Cefazolin; Female; Humans; Minocycline; Sepsis; Staphylococcal Infections; Staphylococcus aureus