The uses of medicinal plants for the treatment of diseases and their effects on rats have been documented. Blood glucose level in oral administration of some antimalarial medicinal plant decoction on Wistar rats was investigated. 36 adult Wistar rats weighing 180±10g were divided into six groups of six each consisting of 3 males and 3 females. The first group of six was given normal diet and water. Each of the other groups received 0.2ml, 0.4ml, 0.6ml, 0.8ml and 1ml of the medicinal plant decoction daily for 7 days. Blood samples were collected from them into oxalate bottles for determination of glucose levels. There was no significant difference between the glucose levels in the control and in the experimental animals. The result of this study can be used as the basis of clinical studies on humans who are diabetic and are receiving treatment for malaria with these medicinal plants.