Alopecia - Should Aldactone be prescribed for thinning hair loss on the scalp?

Yes, spironolactone can be used in female pattern baldness.

Spironolactone is an aldosterone antagonist, and a potassium-sparing diuretic used to treat high blood pressure. Spironolactone is approved as a diuretic but has not been approved as treatment for alopecia, by the FDA.

It has an "off label" use in alopecia, more for female pattern baldness. It inhibits the production of androgens and also blocks the action of androgens at the receptor sites.

Spironolactone can cause decreased libido, impotence, and gynecomastia (excessive development of the male breasts) and is therefore used mainly in women. It can also cause accumulation of potassium in the body (hyperkalemia), which could lead to other serious health problems.

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Common side effects in women are breast tenderness, irregular menses, and mood swings. Women of childbearing age should use effective contraception as there is a possible risk of feminization of the male fetus, should they become pregnant while on spironolactone.

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