To determine the minimum amount of therapy needed to control arterial pressure, the amount of one drug was reduced, then use of one or more drugs was discontinued after the diastolic pressure had been lower than 90 mm Hg for six months in 51 hypertensive patients. By six months, one drug had been eliminated in 38 patients, and the dose of another had been decreased in 49 patients. By 12 months, stepping up therapy was necessary in 13 patients; thus, one drug therapy had been eliminated in only 27 patients, and the dose was decreased in another 43 patients. No further therapeutic changes were necessary during the next six months. Originally, 161 complaints of side effects were noted. After step-down therapy, 18% of the side effects were reported unchanged, 26% were significantly decreased, and 56% were completely absent.