Oyepata Simeon Joseph¹ , Theophilus Adekunle Adegbuyi¹, Joseph Opeyemi Tosin²

Abstract

Purpose: To evaluate the analgesic potential of ethanol stem bark extract of Dennettia tripetala. Methods: Ethanol stem bark extract of Dennettia tripetala was prepared and screened phytochemically using standard procedures. Analgesic activity was assessed in mice (n = 6) using acetic acid-induced writhing test for peripheral nociception and hot plate and radiant heat-tail beat method models for central analgesic activity. Animals received a once-daily dose of 250, 500 and 1000 mg/kg of extract, while diclofenac (50 mg/kg) and morphine (2 mg/kg) served as standard reference drugs. Pain responses were measured as reaction latency and observed number of writhes. Results: The extract produced a significant, dose-dependent reduction in writhing response (23.7 ± 0.22, 17.4 ± 0.54, and 13.3 ± 0.44) compared with control animals (p < 0.05), indicating peripheral analgesic activity. In thermal nociceptive models, extract-treated groups showed significant prolongation of reaction latency times relative to controls (p < 0.05), with the highest dose of 1000 mg/kg producing responses comparable to standard drugs. Phytochemical analysis confirmed the presence of bioactive metabolites associated with analgesic effects. Conclusion: Ethanol stem bark extract of Dennettia tripetala possesses significant central and peripheral analgesic activities, supporting its traditional use in pain management and suggesting potential for development of plant-derived analgesic agents.