A double-blind comparison of trimazosin and metoprolol in patients with mild-to-moderate essential hypertension

The antihypertensive effects and action on the serum lipid profile of trimazosin and metoprolol were compared in an eight-week, double-blind, controlled study. Thirty patients (mean age, 53.7 ± 2.7 years; range, 32-70 years) with mild-to-moderate essential hypertension (standing diastolic blood pressure between 95 and 114 mmHg) were enrolled in the study. After a two-week placebo run-in period, patients were randomly allocated to the trimazosin or the metoprolol eight-week dose-titration period. For both the drugs, an upward dose titration was conducted at two-week intervals. Trimazosin dosage was increased from 50 to 300 mg/day and metoprolol from 50 to 200 mg/day. In the trimazosin group 13 of 15 and in the metoprolol group 11 of 15 (P <0.05) patients had excellent or good overall responses. Quantitative criteria of blood pressure responses indicated that trimazosin was as effective as metoprolol. There were no clinically significant changes in electrocardiogram recordings, chest roentgenograms, or in laboratory tests. Trimazosin, furthermore, significantly (P <0.01) increased the high-density lipoprotein (HDL)-cholesterol serum fraction. No serious side effects occurred in the course of the study: two patients receiving trimazosin complained of tiredness; in the metoprolol-treated group two subjects reported tiredness, one headache, one dryness of the mouth, and one vertigo. No orthostatic hypotension phenomena were observed in either group. Trimazosin, like metoprolol, proved to be a safe and effective antihypertensive drug. Its beneficial effects on the HDL-cholesterol serum fraction may make it a desirable compound of choice in the management of hyperlipemic hypertensives at high coronary heart disease risk.