Some foods interact with drugs, thereby increasing or decreasing the effectiveness of the drugs. The effect of ten vegetables on the pharmacokinetics of Chloroquine (CQ) and Dihydroartemisinin (DHA), used as antimalarial, was investigated.

Extracts of Telfairia occidentalis, Vernonia amygdalina, Gnetum africana, Heinsia crinata, Lasianthera africana, Talinum triangulare, Corchorus olitorius, Ocimum gratisimum, Gongronema latifolium and Amaranthus hybridus (200mg/kg each)were orally co-administered with CQ (10mg/kg) and DHA (2mg/kg), respectively. Concentrations of CQ and DHA were analyzed using UV spectrophotometry in blood collected by cardiac puncture from the rats at 0.5, 1.0, 2.0, 5.0 and 8.0 hrs. Absorption rate (Ka), elimination rate (Ke), area under the curve (AUC), maximum concentration (Cmax), peak time (tmax), half-life (t_1/2), Clearance (Cl), Volume of distribution (Vd) and Bioavailability (F) of the drugs were calculated. Many of the plants affected the pharmacokinetics of the drugs. Telfairia occidentalis altered all the parameters of CQ. It increased Ka, Ke and AUC by 25, 831 and 58%, respectively; reduced t_1/2, tmax, Cl, Vd and F by 91, 64, 37, 94, 96%, respectively. Similarly, the plant increased Ka (by 14%), AUC (58%); reduced t_1/2 (41%)and Vd (by 67%) of DHA. Talinum triangularealtered all the parameters of CQ. It increased Ka, Ke and AUC by 25, 831 and 58%, respectively; reduced t_1/2 (by 91%), tmax (64%), Cl (37%), Vd(94%) and F (96%).