Abstract
In 10 patients with essential hypertension plasma (T-1824) and extracellular fluid volumes (82Brdistribution space), mean blood pressure and serum potassium were determined before treatment, after 2 months of treatment with hydrochlorothiazide and 3 and 6 months of combined thiazide-triamterene treatment. During combined treatment, extracellular fluid volume and mean blood pressure were considerably decreased, whereas the plasma volume reduction was not significant. Serum potassium rose during combined treatment, but was still significantly reduced compared to the control levels. In conclusion, triamterene is a valuable supplement to thiazides in long-term antihypertensive treatment.