Comparative study of hydrochlorothiazide and a fixed combination of metoprolol and hydrochlorothiazide essential hypertension.

In a double-blind study comprising 31 patients with essential hypertension not satisfactorily controlled on hydrochlorothiazide 25 mg o.m., a fixed-ratio combination of metoprolol 100 mg and hydrochlorothiazide 12.5 mg, given as 2 tablets o.m. has been compared with hydrochlorothiazide 50 mg o.m. monotherapy. With the combination regimen a significant reduction of blood pressure was achieved while doubling of the thiazide dose did not adequately control the blood pressure. In 7 patients in the thiazide-group the therapy was changed to the combination during a follow-up period and their blood pressure was normalised. During the follow-up period, 22 patients were thus treated with the fixed combination; 50% of them were controlled on one tablet o.m. The tolerability was good in both groups and no changes were observed regarding laboratory variables except for an increase in serum uric acid in the thiazide-group. The study indicates that a fixed-ratio combination of hydrochlorothiazide 12.5 mg and metoprolol 100 mg in a dose of one or two tablets once daily is a well tolerated and more effective therapy than hydrochlorothiazide 50 mg once daily monotherapy.