Alpha‐ and Beta‐Adrenergic Receptor Blocking Agents Combined with a Diuretic in the Treatment of Essential Hypertension

The antihypertensive efficacy and side effects of the combined therapy with propranolol, phenoxybenzamine, and hydrochlorothiazide were examined in 17 patients with moderate and moderately severe hypertension. Following a control period two to three weeks' duration, propranolol was started in nine patients as the sole antihypertensive agent and together with phenoxybenzamine, in eight. By titrating the dosage against pulse rate and blood pressure response, propranolol was given, in divided doses, from 80 to 160 mg and phenoxybenzamine, from 20 to 50 mg per day. When propranolol was given alone in nine patients, for four to 12 weeks, normal blood pressure was not attained in any patients. During three to ten weeks of combined propranolol and phenoxybenzamine therapy in 17 patients, normal blood pressure (150/90 mm Hg or less) or near-normal pressure (150/100 or less) was attained in 12 patients in the recumbent position and in 15 patients in the upright position, while orthostatic hypotension was not observed. Except for a reduction of ejaculation in three out of six male patients, no other side effects were encountered. The addition of hydrochlorothiazide diuretic in all of the above 17 patients, at a dose of 50-100 mg per day with a concomitant decrease in the dose of phenoxybenzamine, produced a further reduction in blood pressure, and normal or near-normal blood pressure was attained in all subjects. Symptomatic orthostatic hypotension, observed in two patients, was treated by a further readjustment of the dose of phenoxybenzamine, while inhibition of ejaculation was persistent in only one patient. It is concluded that the combined administration of propranolol, phenoxybenzamine, and hydrochlorothiazide in individualized doses is very effective in lowering the blood pressure with minimal side effects.