ACUTE CENTRAL AND PERIPHERAL ANALGESIC ACTIVITY OF ETHANOLIC EXTRACT OF THE LEAVES OF CLERODENDRUM VISCOSUM (EECV) IN RODENT MODELS

Abstract

Pain, inflammation and pyrexia are the most common disturbing symptom a person experiences in life. Numerous drugs are available in the market for relieving these symptoms and which are sold over the counter. However they have high tendency of having adverse drug reaction from a trivial nausea and vomiting to gastric irritation leading to peptic ulcer, perforation and even death. The aim of the study was to investigate the acute peripheral activity of Ethanolic Extract of the leaves of Clerodendrum viscosum(EECV) by acetic acid induced writhing reflex test in mice and acute central analgesic activity by tail immersion method in rats. Dried powdered leaves of Clerodendrum viscosumwere subjected to solvent extraction by using 90 % ethanol. Based on acute oral toxicity study according to Organization for Economic Cooperation and Development (OECD) guidelines No. 423, three doses of the test drug was selected (100, 200 & 400mg/kg for mice) and (75, 150 & 300 mg/kg for rats), and were subjected to acute analgesic activity. The EECV showed significant (p<0.01) acute peripheral analgesic activity in mice in the dose of 200 mg / kg as compared to control but failed to show any central analgesic activity by tail immersion method at any of the three doses selected compared to control in rats.Keyword: Analgesic, Clerodendrum viscosum, Ethanolic extract, Tail immersion test, Writhing reflex test.