Plasma concentration profiles and antihypertensive effect of conventional and extended-release felodipine tablets

1. The rate and extent of felodipine absorption from an oral solution, conventional and extended-release tablets were investigated in two groups of healthy volunteers (n = 18 + 15). 2. The antihypertensive effect of felodipine conventional tablets twice daily (n = 71) and extended-release tablets once daily (n = 76) were compared in a parallel-group study in hypertensive patients. 3. As from a solution, felodipine was completely absorbed from the two solid dosage forms. The rate of absorption increased in the order extended-release tablets, conventional tablets, solution. 4. The extended-release tablet gave more sustained plasma concentrations than the conventional tablet. 5. The extended-release tablet given once daily gave similar blood pressure control to the conventional tablet given twice daily.