Nifedipine GITS replacing nifedipine SR: ambulatory blood pressure assessment of efficacy.

The relative efficacy of two formulations of nifedipine, slow release (SR) and gastrointestinal therapeutic system (GITS), to lower blood pressure in hypertensive patients was evaluated in a prospective study. Nifedipine GITS 30 mg/day replaced nifedipine SR, 20 mg b.i.d. in 38 patients, 23 monitored by routine blood pressure measurements and 15 by ambulatory monitoring. Nifedipine GITS achieved a marked reduction in blood pressure with a smaller dose than nifedipine SR: 30 versus 40 mg/day, respectively. It is concluded that patients with hypertension controlled on a twice-daily dose of nifedipine prolonged action can be converted to a lower once-daily dose of nifedipine GITS without experiencing any increase in blood pressure. Tolerability and compliance improved when switching to the GITS formulation.