Spironolactone is an oral medication frequently prescribed off-label to treat hair loss in women, particularly female pattern hair thinning caused by hormonal or androgen-related factors. Originally developed as a diuretic for blood pressure and fluid retention, spironolactone also has anti-androgen properties, meaning it blocks the effects of hormones like testosterone that can contribute to follicle miniaturization and shedding.
It is commonly recommended for women experiencing diffuse thinning, hormonal acne, or conditions such as Polyendocrine Metabolic Ovarian Syndrome (PMOS). Hair improvement is gradual, with most patients noticing reduced shedding after several months and fuller growth after six to twelve months of consistent use.
Potential side effects may include dizziness, breast tenderness, menstrual irregularities, or increased urination. Because spironolactone can affect hormone balance, it is generally not recommended during pregnancy and should be taken under medical supervision.