efficacy of etoricoxib on peripheral hyperalgesia

Conditions: Causalgia; Polyneuropathy; Postherpetic Neuralgia; Peripheral Nerve Injury; Radiculopathy

Summary: the purpose of the study is to determine the efficacy of etoricoxib on pain patients. the investigators assume that patients with neuropathic pain will have greater pain relief then patients on placebo.

animal experiments analysing anti-hyperalgesic effects of coxibs show inconsistent results due to different used dosages and varying different pain models. theoretical the use of nsaids is rational, particularly of coxibs as a part of the neuropathic pain management. but in the newest topical review, there is no valid information available about the effectiveness of these drugs in human neuropathic pain models or in patients with different underlying mechanism, e.g. with or without hyperalgesia.

Eligibility criteria:
inclusion criteria: * patients over 18 years with * persistent moderate or severe pain (\> 4 on nrs (1..10)) at rest (average of three daily assessments using a diary for at least two days) . * neuropathic pain associated with a clinical and neurologically proven peripheral nerve injury, radiculopathy, postherpetic neuralgia or polyneuropathy or crps * one of the two following qst phenotypes at the baseline assessment: * signs of peripheral hyperalgesia (that means, pathological decreased heat pain threshold and/or pathological decreased muscle pain threshold) * without signs of peripheral hyperalgesia (no pathological decreased heat - and/or muscle pain threshold) * patients of both gender * signed consent form * patients with the ability to understand and follow the instructions of the doctor exclusion criteria: * excluded will be patients parkinson's disease or a history of cerebral vascular insult or nerve injury. excluded will be also all patients with contradictions for the use of etoricoxib: * hypersensitivity to the active substance or to any of the excipients. * active peptic ulceration or active gastrointestinal (gi) bleeding. * patients who have experienced bronchospasm, acute rhinitis, nasal polyps, angioneurotic oedema, urticaria, or allergic-type reactions after taking acetyl-salicylic acid or nsaids including cox-2 (cyclooxygenase-2) inhibitors. * pregnancy and lactation * severe hepatic dysfunction (serum albumin \<25 g/l or child-pugh score ≥10). * estimated renal creatinine clearance \<30 ml/min. * inflammatory bowel disease. * congestive heart failure (nyha ii-iv). * patients with hypertension whose blood pressure is persistently elevated above 140/90mmhg and has not been adequately controlled * established ischemic heart disease, peripheral arterial disease, and/or cerebrovascular disease. * intake of one of the following drugs (current or in the last 3 days) * selective-serotonin-reuptake-inhibitor * cetoconazole * rifampicin * phenytoin * carbamazepine * dexamethasone or other systemic corticoids * traditional nonsteroidal antiphlogistics * cyclooxygenase-inhibitors * immunosuppressives * tnf-α-inhibitors

Keywords: crps morbus sudeck causalgia etoricoxib polyneuropathy post herpetic neuralgia peripheral nerve injury radiculopathy nervenverletzung postherpetische neuralgie cox-2-inhibitor