OBSERVATIONS ON TRIAMTERENE—A NEW DIURETIC

SUMMARY In subjects without cedema, triamterene given orally caused increased urinary excretion of sodium and chloride, but not of potassium, in the 12 hours following administration, but continued administration produced no effect on the 24‐hour electrolyte excretion. In a short‐term trial, in which patients were treated for four‐day periods with triamterene, chlorothiazide and combined therapy, triamterene and chlorothiazide had similar effects on weight loss and sodium excretion, but there was less loss of potassium with triamterene. Combination of the two drugs resulted in increased excretion of sodium, but not in weight loss or larger urine volume. In the long‐term treatment of refractory cedema, triamterene alone was unavailing, but when combined with chlorothiazide or with chlorothiazide plus spironolactone, it was of distinct value. The dose required (450 mg. per day) was higher than that used by other workers (100 to 300 mg. per day). No side effects were observed which could be attributed to the drug.