Abstract

ANTIPYRETIC ACTIVITY OF METHANOLIC LEAF EXTRACT OF ANDROGRAPHIS PANICULATA ON BREWER’S YEAST INDUCED PYREXIA IN EXPERIMENTAL ANIMALS

Akintola A. O.*, Kehinde B. D., Adeyi R. O., Adewoyin A. G.

ABSTRACT

The antipyretics in common use include acetaminophen, aspirin and other non steroidal anti inflammatory drugs (NSAIDS). Most of these antipyretic drugs inhibit the enzyme cyclooxygenase 2 (COX-2) with high selectivity but are toxic to the hepatic cells, glomeruli cortex of the brain and heart muscles whereas natural COX-2 inhibitors have lower selectivity with fewer side effects. A natural antipyretic agent with reduced or no toxicity is therefore essential. The present study was designed to evaluate the antipyretic activity of the methanolic leaf extract of Andrographis paniculata on brewer’s yeast induced fever in experimental rats. A total number of 25 albino rats (200g) were used for the study. They were divided into five groups of five rats each. Group I served as control and was given brewer’s yeast alone, group II was given 150mg/kg of paracetamol and while groups III, IV and V were treated with 50mg/kg, 100mg/kg and 200mg/kg of Andrographis paniculata extract respectively. Pyrexia was induced by subcutaneously injecting 20% w/v brewer’s suspension (20mL/kg) in the back below the nape of the neck of the animals. Twenty four hours after the injection, the rectal temperature of each was measured. Andrographis paniculata (50mg/kg, 100mg/kg and 200mg/kg) and paracetamol (150mg/kg) were administered orally. The rectal temperature was measured at 30, 60, 90 and 120 minutes after drug administration. Andrographis paniculata (200mg/kg) significantly (p < 0.05) reduced yeast induced pyrexia (34.68± 0.10C) when compared with Group I (20mL/kg brewer’s yeast) with temperature of 38.98 ± 0.370C. Group II (paracetamol, 150mg/kg) also show significant reduction of 35.15 ± 0.170C when compared with Group I. This experiment shows that the antipyretic effect of Andrographis paniculata leaf extract is dose dependent. It is concluded that the crude methanolic extract of Andrographis paniculata have significant antipyretic activity when compared with the standard drug and this strongly support the ethnopharmacological use of the plant for the management of fever.

Keywords: Antipyretic activity, methanolic extract, brewer’s yeast Andrographis paniculata, pyrexia.