Captopril and hydrochlorothiazide in the fixed combination multicenter trial.

The severe side effects uncommonly seen with captopril seem to be associated with high doses and/or compromised patients. A very flat dose-response curve in high dosages and the expectation of fewer side effects made us combine low-dose captopril with enhanced stimulation of the renin-angiotensin-aldosterone (RAA) system. Methods used were as follows: (a) In 43 patients (25 female, 18 male, age 45 +/- 10) with inadequate lowering of blood pressure or side effects due to therapy, we started a combination therapy with the fixed combination of captopril 25 mg + hydrochlorothiazide (HCTZ) 25 mg twice a day after a washout phase of 14 days. If blood pressure was not lowered satisfactorily, we increased the dosage to a fixed combination of 50 mg captopril + 25 mg HCTZ for 6 months. (b) In 12 patients (eight male, four female, age 47 +/- 7) an initial high-dose treatment of captopril (3 X 50-3 X 150 mg, mean = 325 +/- 87 mg/day in combination with small doses of diuretics) was changed to low-dose captopril (2 X 50 mg, mean = 96 +/- 14 mg/day; dose reduction: 70%!) in a fixed combination with 25 mg HCTZ in each tablet. Results obtained were as follows: (a) Initial blood pressure values of 189/106 +/- 28/7 mm Hg fell to 160/84 +/- 23/12 mm Hg after 2 weeks. Systolic pressure decreased further to 146 +/- 20 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)