The Effects of Carbonic Anhydrase Inhibitor in Addison's Disease

INTRODUCTION  It has been shown that the distal tubule of the kidney is a site of action of both the adrenal hormones and carbonic anhydrase.* The inhibition of carbonic anhydrase in the kidney causes an increase in urinary pH, bicarbonate, sodium, and potassium and a decrease in urinary ammonia.† In the blood there is a fall in arterial pH and plasma bicarbonate and some decrease in plasma potassium, with no change noted in the plasma sodium.¹¹Increased urinary potassium excretion is an effect which is also seen with the administration of the adrenal steroids. The exact mechanism of the action of the adrenal hormones within the renal tubule is yet unproved, although a mechanism is suggested by Pitts.¹² It was felt that the administration of a carbonic anhydrase inhibitor, acetazoleamide (Diamox),‡ to patients with adrenal insufficiency might provide further information with regard to the renal activity of both