Aim: In this chapter the influence of selected dose of Allium sativum (84 mg/1.5 kg bd.wt) on the pharmacodynamics and pharmacokinetics of selected dose of gliclazide (5.6 mg/1.5 kg bd.wt) were studied in normal rabbits. Materials & Methods: Materials required were purchased from Sai Chemicals, Visakhapatnam, India. Inbred adult wistar rabbits of either sex were used for the study. Gliclazide (TD) was administered orally to all the rabbits. After a wash out period of one week the same groups of animals were administered with Allium sativum (84 mg/1.5 kg bd.wt.) orally. Again after a further washout period of one week, the same group was administerd with Allium sativum (84 mg/1.5 kg bd.wt.) orally, 30 min prior to the administration of gliclazide (5.6 mg/1.5 kg bd.wt). Blood samples were withdrawn at 0, 1, 2, 3, 4, 6, 8, 12, 16, 20 and 24 h intervals from marginal ear vein puncture and were analyzed for blood glucose by GOD/POD method in all the experiments and serum gliclazide. Results: Allium sativum has found to enhance the hypoglycaemic effect of gliclazide. The percent blood glucose reduction with gliclazide (5.6 mg/1.5 kg bd.wt) before and after treatment with Allium sativum(104 mg/Kg) in rabbits. Conclusion: The interaction between Allium sativum and gliclazide appears to be pharmacodynamic and pharmacokinetic in nature