Isradipine in essential hypertension: the Belgian General Practitioners' Study

Abstract

Over 200 hypertensive patients were recruited by 37 general practitioners into a single-blind 12-week study to assess the efficacy, tolerability, and safety of isradipine as an antihypertensive, alone and in combination with guanfacine. A total of 212 patients were given isradipine at doses of 1.25 and 2.5 mg twice daily. Twelve hours after the last dose, diastolic blood pressure was reduced to no more than 90 mm Hg in 52.6 percent of patients treated with isradipine alone. After eight weeks of treatment, 30 percent of patients were also given guanfacine 1 mg daily. By Week 12, 67.6 percent of the patients had attained normotension. Compared with placebo, side-effect frequency was higher for flushing and edema with isradipine, and dry mouth was more frequent with added guanfacine. Electrocardiographic examinations and routine laboratory determinations showed no clinically relevant changes. These data indicate that isradipine as monotherapy and in combination with guanfacine is an effective antihypertensive agent. Most patients will continue to participate in a two-year follow-up involving bimonthly clinical visits and half-yearly electrocardiographic examinations and laboratory determinations.