Single-agent and combination therapy of essential hypertension.

Patients with mild to moderate essential hypertension were treated with beta-blockers and diuretics given separately and in combination. During single-drug therapy, the majority of patients exhibited clearly superior antihypertensive responses to either one type of drug or the other; only rarely were the beta-blockers and the diuretic equally effective in an individual patient. A poor response to diuretic therapy tended to predict a good response to a beta-blocker, and vice versa. Pretreatment renin measurements were not helpful in predicting the differing responses to single-drug treatment in this study population. These findings indicate that when one of these types of drug is ineffective as monotherapy in treating hypertension, the other type should be substituted before considering combination treatment. Combined therapy with the beta-blockers and diuretics also gave variable results, although poor antihypertensive responses could be attributed to excessive stimulation of the renin-aldosterone system by the diuretic component of the combination. The effectiveness of this form of treatment might thus be enhanced by the use of low diuretic doses.