Analgesic profile of peroral and topical ketoprofen upon low pH-induced muscle pain

摘要: Topical analgesics are widely marketed for treatment of muscle and joint pain. We have recently developed a model pain used this to evaluate the efficacy commercially available topical peroral ketoprofen in order time- dose-dependence analgesia. In present study, we examined dose- (0, 50, 100 mg) time-dependence (hourly 8 h) ketoprofen. achieve infusion times h (and thus study time course analgesic action), adapted low pH-induced humans these requirements by applying infusions continuously 10 min every hour h. found that produced reliable consistent levels were reproducible over study. The was performed double-blind, randomized, with 1-week interval between each five different sessions (cross-over). Altogether six volunteers underwent intramuscular isotonic phosphate-buffered saline solution pH 5.2; during session switched on eight duration at 50 intervals (there no interval). phosphate buffer induced localized dull-aching or stinging sensation; flow rate individually adjusted induce magnitude 20% visual analogue scale (ranging from ‘no pain’ (0%) ‘unbearable (100%)). Twenty minutes after starting received capsule either placebo mg perorally and, addition, gel 2.5% commercial applied topically skin. One included an oral placebo. intensity recurrent stimulus significantly reduced 59% following administration within first 3 (P<0.03, Wilcoxon test); analgesia lasted up sixth experimental protocol. Oral (50 less effective 45% (P<0.05) only second third hour. contrast, reduction application not same but appeared be faster develop (with maximum effect 1 average. suppression 51% (significant P<0.03), while non-significant 29%. apparent rapid transient ratings increased back baseline values dose 2 dose. This data suggests gel-based systems does provide long-lasting when compared perorally-dosed show even doses do complete relief