[Sexual side-effects of spironolactones. Possible mechanisms of their anti-androgen action].

Spirolactones (spironolactone, potassium canrenoate) may produce secundary sexual effects such as gynecomastia in man and menstrual disturbances in women. The mechanism of action of the antiandrogenic effects has been studied in man and rat. Acute i.v. injection of potassium canrenoate into man results in a decrease of plasma testosterone, without any change of gonadotropins. This decrease might be due to an impaired testicular steroidogenesis. On the other hand, spirolactones have an antiandrogenic effect at the target cells level. They do not modify the prostate 5alpha-reductase activity; however, they do inhibit the binding of androgens to their receptors. Thus the spirolactones interact with both biosynthesis and peripheral action of androgens.