Plumbago zeylanica action on blood coagulation profile with and without blood volume reduction

Plumbago zeylanica (PZ) is extensively used in Indian systems of medicine for its medicinal properties. The structure of its active principle is similar to that of vitamin K. Its effect on blood coagulation profile after chronic administration has not been reported so far. The PZ extract (2 mg/kg body weight) and napthoquinone (2 mg/kg body weight) given to individual groups were screened for its effect on bleeding time (BT), clotting time (CT), prothrombin time (PT), platelet count and platelet adhesion in albino rats after 1-day, 15-day and 31-day treatment. There was no change in the platelet count in the treated groups when compared to the control levels. But the platelet adhesion was significantly decreased after PZ and also napthaquinone-treated animals in both with and without blood volume reduction after 15th as well as 31st day. Since the napthoquinone-treated group also showed similar response the changes observed after PZ treatment may be due to this component. Even at a lower dosage level (2 mg/kg body weight), the chronic PZ administration prolongs the bleeding time by altering platelet adhesiveness and the coagulation.