First clinical experience with isradipine in the treatment of hypertension in Portugal.

The efficacy and safety of isradipine and nifedipine retard were compared in 51 patients with mild-to-moderate essential hypertension. A 4-week placebo run-in period was followed by an 8-week course of treatment. Patients were randomly allocated to either isradipine 1.25 mg twice daily (n = 24) or nifedipine 20 mg twice daily (n = 826); dosages were doubled if blood pressure was not normalized [diastolic blood pressure greater than or equal to 90 mm Hg) after 4 weeks of active treatment. Systolic/diastolic blood pressures were significantly reduced (p less than 0.01/p less than 0.01) by isradipine from 162/103 to 145/89 mm Hg, and by nifedipine from 162/104 to 143/88 mm Hg. Normalization rates were 79% with isradipine and 67% with nifedipine. It was necessary to double the dosage in seven of the patients taking isradipine and in three of those taking nifedipine; the mean final dosages were 1.63 mg and 22.4 mg twice daily, respectively. Heart rate did not change significantly with either treatment. There were drug-related adverse events in five patients (21%) taking isradipine (2 edema, 2 headache, 2 palpitations, 1 flushing) and in eight (30%) of those taking nifedipine (5 edema, 2 headache, 1 palpitations). Therapy was withdrawn in one patient in the isradipine group (1 headache) and two patients in the nifedipine group (1 edema, 1 headache). We conclude that isradipine is a highly effective and well tolerated antihypertensive agent.