Isradipine: overall clinical experience in hypertension in the United States

Isradipine is a new dihydropyridine calcium antagonist shown to be efficacious, safe, and well tolerated in the treatment of hypertension, regardless of patient age or race. There has been no evidence of negative inotropism, atrioventricular conduction delay, nor clinically significant changes in laboratory parameters associated with isradipine treatment. A total of 934 patients have been treated with isradipine in double-blind hypertension trials (involving 297 patients treated with placebo and 414 treated with active controls, such as hydrochlorothiazide and enalapril). Both the mean changes from baseline in diastolic and systolic blood pressures and the percentage of patients responding to treatment (blood pressure decrease of at least 10 mm Hg) were greater with isradipine than with placebo or active controls. Blood pressure response increases with increases in isradipine dose up to 10-15 mg daily; higher doses do not, on average, result in greater blood pressure reduction. The incidence of adverse reactions with isradipine is similar to that for active controls and slightly more than for placebo. There were fewer discontinuations with isradipine and, in addition, the incidence of new adverse reactions decreased with increasing duration of treatment, down to 1% at 24 months.