LONG TERM SPIRONOLACTONE AND THE ADRENAL CORTEX IN ESSENTIAL HYPERTENSION

Abstract

Spironolactone (''Aldactone''-Searle) is a potassium-sparing diuretic widely used in the treatment of hypertension and primary and secondary aldosteronism. In view of recent evidence that spironolactone may inhibit synthesis of corticosteroids by a direct effect on the adrenal cortex, adrenocortical function was studied in 8 patients with essential hypertension who had been treated with spironolactone from 3 mo. to 14 yr. Their 24 h renal excretion of adrenocorticoid metabolites and the responses of cortisol, aldosterone and 18-hydroxy-11-deoxycorticosterone (18-OH-DOC) to an incremental infusion of tetracosactrin (1-24 ACTH) were compared with those in 8 patients with recently diagnosed essential hypertension who had received no spironolactone. The spironolactone-treated group had a significantly higher excretion of aldosterone, while the excretion of other adrenocorticoid metabolites did not differ. The same group also required less tetracosactrin to stimulate a detectable rise of plasma cortisol and 18-OH-DOC, they had greater plasma 18-OH-DOC responses at all infusion rates and, at the lowest infusion rates, had greater aldosterone responses. The results indicate that long-term spironolactone therapy does not inhibit adrenocortical function and may have some stimulatory effects.