title: Controlled clinical trial of cadralazine as a second-step drug in the treatment of hypertension.
abstract: The antihypertensive efficacy of a new long-lasting vasodilator, cadralazine, and the diuretic chlorthalidone have been compared in hypertensive patients receiving concurrent treatment with atenolol. After a 4-week run-in period with atenolol alone 100 mg/day, two groups of 10 patients whose diastolic blood pressure exceeded 100 mm Hg were given for a period of 65 days either cadralazine 15 mg/day or chlorthalidone 25 mg/day, according to a randomized, double-blind, between-patients design. Compared to atenolol alone, both cadralazine and chlorthalidone induced a statistically and clinically significant decrease in blood pressure. The antihypertensive effect did not differ significantly between groups. Good compensation of the atenolol-induced decrease in heart rate was obtained with cadralazine, whereas during atenolol + chlorthalidone treatment at times the standing heart rate was significantly lower than during treatment with atenolol + cadralazine. Side-effects, many of which were already present during atenolol treatment, occurred with a similar frequency in both groups. It is concluded that atenolol + cadralazine and atenolol + chlorthalidone are equally well tolerated, acceptable and effective in the treatment of hypertension, but that further studies are warranted to explore the potential haemodynamic advantages of the cadralazine + atenolol combination.
mesh_terms: D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001262:Atenolol / Q000008:administration & dosage; D001794:Blood Pressure / Q000187:drug effects; D002752:Chlorthalidone / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D004359:Drug Therapy, Combination; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D011724:Pyridazines / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D000959:Antihypertensive Agents; D011724:Pyridazines; D001262:Atenolol; C031877:cadralazine; D002752:Chlorthalidone