Antipyretic Activity of Methanolic Leaf Extract of Acalypha Wilkesiana (Copper Leaf) On Wistar Rats

Acalypha wilkesiana is an ornamental plant that is generally referred to as copper leaf and it is a shrub with mostly glossy green or red leaves. It is used in the management of fever in infants locally. Wistar rats weighing 150-200g were divided into six groups (n=5). Group 1 (control) was administered brewer's yeast (40mg/kg) , group 2 was administered brewer's yeast and aspirin (100mg/kg), while groups 3, 4 and 5 were administered 100, 200 and 300mg/kg of Acalypha wilkesiana respectively. Initial rectal temperature was taken before admistration of brewer's yeast. Brewer's yeast was injected subcutaneously to induce fever in the test groups. Temperature was measured after 18hours using rectal thermometer at 0, 1, 2, 3 and 4 hours after the extract and standard drug were administered. Group 5, 4 and 3 (300mg/kg, 200mg/kg and 100mg/kg) significantly reduced brewer's yeast induced pyrexia, (36.46±0.21, 36.90±0.31 and36.84±0.22), when compared with the positive control (brewer's yeast) (37.96±0.22). Group 2 (Aspirin 100mg/kg) also showed significantly reduced brewer's yeast induced pyrexia (36.88 ±0.22) when compared with the positive control (brewer's yeast) (37.96±0.22). This study shows that the antipyretic effect of Acalypha wilkesiana is dose dependent, being most effective at the high dose (300mg/kg). This suggests that the methanolic extract of Acalypha wilkesiana leaves possesses significant antipyretic activity which is dose dependent and its mechanism could be due to the presence of flavonoids, saponins and alkaloids.