Spironolactone for Hair Loss: How It Works for Women

Spironolactone is one of the most commonly prescribed treatments for female pattern hair loss. It's an oral anti-androgen that blocks the hormonal signals driving thinning in women — and while it's used off-label for hair, it has years of dermatology use behind it. It isn't used in men, and it works gradually over six months or more.

How it works for hair

Spironolactone blocks androgen receptors and reduces the effect of testosterone. In women whose hair loss is androgen-driven — including many cases of female pattern hair loss and PCOS-related shedding — that dampens the hormonal miniaturization shrinking the follicles, helping preserve and sometimes modestly improve density.

Who it's for

It's generally prescribed for women with female pattern hair loss, particularly those showing signs of excess androgens such as PCOS, acne, or unwanted facial hair. Clinicians usually rule out other causes first — thyroid problems and low iron are common culprits — before reaching for an anti-androgen.

• Women with androgenetic / female pattern hair loss
• Thinning linked to PCOS or other signs of excess androgens
• Often used after iron and thyroid causes have been excluded
• Not used in men, due to feminizing effects

What to expect

Doses are started low and adjusted. Hair results take 6–12 months, and treatment is ongoing — stopping generally reverses the benefit. It's frequently combined with a reliable form of contraception, both because pregnancy is a contraindication and, in some cases, for added anti-androgen benefit.

Side effects in brief

The common ones are increased urination, menstrual changes, breast tenderness, and mild dizziness, with potassium being the lab value doctors monitor. These are mostly dose-related and manageable under supervision — covered in detail in our guide to spironolactone side effects.