Clinical experience with ketanserin in the treatment of hypertension

Ketanserin (K), a selective and specific S2-receptor antagonist, has been compared with metoprolol (M), a cardioselective beta-blocker, in a double-blind study in order to assess its efficacy and safety in the treatment of essential hypertension. After a placebo run-in period of 4 weeks, hypertensive patients [supine diastolic blood pressure (DBP) greater than or equal to 100 mmHg] were treated with K, 40 mg twice daily (n = 18), or with M, 100 mg twice daily (n = 14). Systolic pressure (SBP) and DBP, both supine and standing, were significantly reduced from the first month of treatment by both drugs and remained stable for the whole study period (12 weeks). About two-thirds of the patients treated with K responded to the therapy (drop in DBP of at least 10%) and half were normalized (DBP less than or equal to 90 mmHg). In the M group, 50% of patients responded and 30% were normalized. A significant decrease in the heart rate was observed with M, but not with K. Ten patients treated with K were followed for 1 year. The antihypertensive effect of K was maintained throughout the study with evidence of tolerance. No serious adverse reaction was observed.