Antihypertensive effect of oral timolol maleate and hydrochlorothiazide once daily compared with hydrochlorothiazide once daily.
The efficacy and safety of timolol maleate combined with hydrochlorothiazide given once daily compared with hydrochlorothiazide given once daily to patients with hypertension was investigated in a double-blind, randomized study. Patients with uncomplicated, mild to moderate hypertension were admitted to the study. Ten patients received two tablets once daily of timolol maleate 10 mg and hydrochlorothiazide 25 mg (T/H). Nine patients received hydrochlorothiazide 25 mg (HCTZ). Blood pressure and pulse rate measurements and laboratory tests were performed after a six-week placebo baseline period and throughout the 12-week study. Mean supine systolic blood pressure decreased by 21-35 mm Hg for the T/H group and by 10-24 mm Hg for the HCTZ group. Mean supine diastolic blood pressure decreased by 15-22 mm Hg for the T/H group and by 10-13 mm Hg for the HCTZ group. Changes observed in the laboratory variables were not statistically significant between the two treatment groups. One patient in each group had an adverse experience considered unrelated to the drug, and no patient had to discontinue the drug therapy because of an adverse reaction. Although both drug regimens effectively and safely treated uncomplicated mild to moderate hypertension, the timolol maleate and hydrochlorothiazide combination had a greater antihypertensive effect.