Comparative assessment of first-line agents for treatment of hypertension

Abstract To compare the safety and efficacy of isradipine as an antihypertensive drug, five studies were performed with other antihypertensive drugs. In each, isradipine was given in doses of 2.5 to 10 mg twice daily and its effects were compared with those of placebo, propranolol, prazosin, and hydrochlorothiazide. The studies were randomized and double-blinded, employing either a fixed or forced titration. Studies were designed with a three-week placebo washout period followed by four to 10 weeks of active therapy. Isradipine was administered to 288 patients and resulted in a mean decrease in diastolic blood pressure of 16.2 mm Hg; in 81 percent of the patients it decreased by more than 10 mm Hg. Corresponding values for the other drugs tested were: placebo (n = 78), 5.9 mm Hg and 32 percent; propranolol (n = 31), 9.8 mm Hg and 39 percent; and prazosin (n = 33), 13 mm Hg and 69 percent. Isradipine was generally well tolerated, with few reported side effects.