Addition of chlorthalidone to slow-release nifedipine in the treatment of arterial hypertension: a controlled study versus placebo.
The use of calcium antagonists and diuretics in combination for treatment of hypertension is controversial. In a single-blind study 16 patients (8 men, 8 women, age range 39 to 62 years) with primary hypertension of mild to moderate degree were given slow-release nifedipine 20 mg twice daily for 6 weeks, thereafter either chlorthalidone 25 mg (Group A) or placebo (group B) daily was randomly added for a further 6-week period. Blood pressure (BP), heart rate, plasma renin activity (PRA), aldosterone, and 24 hour urinary electrolytes were evaluated. Nifedipine decreased supine BP from 159/92 +/- 16/8 to 151/89 +/- 10/6 mmHg in group A and from 162/94 +/- 20/12 to 145/85 +/- 14/6 mmHg in group B. A further fall to 139/84 +/- 7/6 mmHg (p less than .05) was observed after addition of chlorthalidone. PRA significantly increased with combined treatment compared to baseline (3.3 +/- 0.8 to 9.9 +/- 3.3 ng/ml/hr; p less than 0.05). A slight reduction of 24-hour urinary calcium was observed after the addition of chlorthalidone. These data indicate that the combination of nifedipine and chlorthalidone might be beneficial in the treatment of arterial hypertension.
Ferrara
L A
LA
Institute of Internal Medicine and Metabolic Diseases--Second Medical School, University of Naples, Italy.
Marotta
T
T
Pasanisi
F
F
Mastranzo
P
P
Mancini
M
M
D000328:Adult; D002752:Chlorthalidone / Q000627:therapeutic use*; D003692:Delayed-Action Preparations; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000008:administration & dosage / Q000627:therapeutic use*; D016037:Single-Blind Method
D003692:Delayed-Action Preparations; D009543:Nifedipine; D002752:Chlorthalidone