The Effect of Ethanolic Extract of Vernonia Amygdalina Leaves on Some Pharmacokinetics Parameters of Chloroquine in Rats

Studies were done to find out if there are significant pharmacokinetics interactions between chloroquine and ethanolic extract of Vernonia amygdalina when the extract was administered 1 h before chloroquine or simultaneously with chloroquine to different groups of albino rats (Wister strain). Three groups of rats were used, each group comprising 25 rats with one group acting as control. The chloroquine level in the serum was measured using UV-spectrophotometer. The results indicate significant interactions (p< 0.05) in the groups to which the extract was administered simultaneously with chloroquine. There was a decrease in the level of drug in circulation as evidenced by the lower values of AUC (297.52 8.45 vs. 333.22 24.99) and Cmax (74.6 1.02) vs. 76.6 3.07) comparing experimental group with control. There was increased rate of elimination of the drug between the experimental group and control (Ke 0.088 0.035 vs. 0.027 0.017). There was no significant pharmacokinetics interactions (p>0.05) when the extract was administered 1 h before chloroquine. The result indicate that concomitant administration of chloroquine and Vernonia amygdalina resulted in significant interactions (p<0.05) and should be avoided to maintain a good plasma level of the drug and prevent possible development of resistance by Plasmodium due to sub-clinical concentration of the drug in the blood.