Potassium-Sparing Effects of Triamterene in the Treatment of Hypertension

Abstract

Triamterene (2,4,7-triamino-6-phenylpteridine) was employed alone and in combination with hydrochlorothiazide in the treatment of patients with group 1 and 2 hypertension. In 21 patients, triamterene alone had an inconsistent antihypertensive effect on the systolic blood pressure, which was minimal in most patients. In 16 patients the combination of triamterene and hydrochlorothiazide (2:1 by weight) reduced the systolic blood pressure slightly more than did hydrochlorothiazide alone. Triamterene alone or in combination with hydrochlorothiazide produced an increase in the concentration of potassium in serum. Side effects due to triamterene were similar to those noted with thiazide diuretics. In addition, five patients had a decrease in blood hemoglobin concentration, and two patients had reversible alterations in liver function during triamterene therapy. Triamterene may be a useful adjunct for thiazidetreated hypertensive patients by decreasing the likelihood of complicating hypokalemia.