Diabetes and high blood pressure tend to occur together because they share certain physiological traits.Most patients with diabetes will require combination therapy with multiple antihypertensive drugs to achieve good control. Metformin is widely used in Nigeria to manage Type II diabetes. 1000 mg of metformin was administered alone and with 30 mg of Nifedipine to patients newly diagnosed for diabetes with hypertension. The wash out period was two weeks. HPLC method was used to analyse the serum samples of the patients using Hypersil C18 column at a wavelength of 238 nm. Solvent system was acetonitrile with methanol and buffer. Plasma glucose levels were determined using the standard glucose oxidase method. The maximum absorption concentration of Metformin increased significantly, p˂0.05 from1890.67 ± 0.22 ng/ml when administered alone to 2357. 16 ± 0.5 ng/ml when co-administered with nifedipine at maximum absorption time of 3 hrs. Area under curve of plasma drug concentration time curve San(AUC)0-8h also significantly increased from 8882.10 ng/ml/h alone to 10724.57 ng/ml/h when interacted with nifedipine, p˂0.05. All other pharmacokinetic parameters were not significantly altered. The increased absorption increased the AUC. The effects were followed with non- significant increase in hypoglyceamic effect. Diabetic patients on metformin can be prescribed nifedipine without risk of side effects.