Pharmacokinetics and pharmacodynamics of two commercial oral nifedipine products.

Nifedipine, a calcium channel blocker, is widely used in the management of hypertension, angina and cardiac arrhythmias. In this study, the bioequivalence of two pharmaceutical formulations of nifedipine, Nifecard (10 mg capsules) manufactured by Dar Al-Dawa Development and Investment Co, Ltd. and Adalat (10 mg capsules) manufactured by Bayer Pharmaceutical Company, was assessed in twelve healthy male subjects. Nifecard or Adalat was given orally on two occasions separated by one week wash-out interval. Blood samples for the determination of plasma nifedipine concentration were taken for 8 hours following drug administration. Blood pressure and pulse were also measured after each treatment. Plasma nifedipine concentrations were measured by a simple, sensitive and reproducible HPLC method. There were no significant differences in oral absorption, Cmax, tmax, t1/2 and AUC between Nifecard and Adalat. Also, Nifecard and Adalat produced similar hemodynamic profiles (blood pressure and pulse). In conclusion, our results demonstrate that both Adalat and Nifecard are bioequivalent and produced similar pharmacological effects.