A recent in-vitro study found that PPI inhibit metformin uptake by organic cation transporters (OCTs). This drug-drug interaction the clinical has the potential relevance of consequences on metformin disposition and/or efficacy. Since there is a possibility for the combined use of metformin and omeprazole in chronic diabetics, the study is planned to investigate the effect of nicorandil on the activity of gliclazide in normal and diabetic rats to evaluate effectiveness of the combination.