The effect of the root bark extract of Ceiba pentandra
(Linn) in normal and streptozotocin-induced diabetic rats was studied. Blood glucose levels were determined after oral administration of graded doses of C. pentandra
(40, 75,150 and 300 mg/kg) in fasted normal and diabetic groups. In both groups, 40 and 75 mg/kg of the extract, significantly reduced blood glucose levels 8 h after administration, which was consistent and time-dependent. C. pentandra at the lower dose of 40mg/kg produced blood -glucose-lowering effect of 40.0% and 48.9%, in normal and diabetic rats respectively when compared with control rats. The higher doses of 150 and 300 mg/kg did not affect significantly the blood glucose levels. In multiple dose studies, the diabetic rats were treated orally by gavages, twice a day for 3 days. On day 3, C. pentandra
(40 and 75mg/kg) significantly decreased blood and urine glucose levels as compared to initial values. The 14 h fasting blood glucose concentration was lowered by 59.8 % and 42.8% at the doses of 40 and 75 mg/kg and the corresponding urine glucose levels reductions were 95.7% and 63.6%, respectively. The results indicated that C. pentandra
possessed hypoglycaemic effect. The plant extract was capable of ameliorating at lower doses, hyperglycaemia in streptozotocin-induced diabetic rats and could be a potential source for isolation of new orally active agent(s) for anti-diabetic therapy.