Background: Diabetes mellitus (DM) is a spectrum of common metabolic disorders characterized by hyperglycemia. Ranolazine is an active piperazine derivative, used as a first line agent in the treatment of chronic stable angina, either as a primary agent or as an adjunct to ongoing amlodipine, beta-blocker and nitrate therapy.4 According to the CARISA (Combination Assessment of Ranolazine in Stable Angina) trial and its long-term open-label extension study, ranolazine significantly decreased HbA1c values in patients with diabetes.5,6 However, there are only few reports of experimental evaluation of the antihyperglycemic effect of ranolazine in rats. Hence, we have decided to undertake this study to evaluate the antihyperglycemic effect of ranolazine in rats with experimentally induced diabetes mellitus.