Improvement of renal function during long-term treatment of severe hypertension with minoxidil.

Sixty-nine patients with refractory hypertension were treated with minoxidil and in 66 good control of blood pressure was achieved. Renal function was stabilized in 31 patients in whom the serum creatinine was normal at presentation. Twenty-eight patients with impaired renal function had a substantial fall in serum creatinine (25 per cent) during the first three to six months of treatment and this improvement was maintained. In contrast, renal function in six out of seven patients with primary renal disease continued to deteriorate despite adequate control of blood pressure. Effective control of blood pressure prevents or reverses impairment of renal function in patients with refractory hypertension not associated with primary renal disease.