What Is Spironolactone?
Spironolactone is an orally administered anti-androgen drug used off-label for women with female pattern hair loss (FPHL). It works in 3 ways to help thinning hair:(15, 203)
- Blocks the androgen hormone DHT from attaching to hormone receptors at hair follicles. DHT triggers cellular and genetic activity that stimulates hair loss.
- Inhibits the production of excess androgen hormones by the adrenal gland.
- Stimulates the conversion of free testosterone to estrogen (beneficial to hair growth).
Does Spironolactone Work for Thinning or Excess Hair?
Results from a clinical study in Australia found that spironolactone helped some women with FPHL. Treatment was for at least 12 months with either spironolactone or cyproterone acetate. Most of the 80 women participating in the study showed some relief from hair loss:(205)
- 44% regrew some hair
- 44% had no clear change in hair density but no additional hair loss
The remaining 12% of participants continued to lose hair during the study.(205)
The drug can also reduce hirsutism in women with polycystic ovary syndrome (PCOS), a condition that can also cause scalp hair loss. Clinical data shows 100 mg/day of spironolactone performs better than either finasteride or cyproterone acetate for excess hair in women with PCOS.(15)
Dosing Information for Spironolactone
Spironolactone dosages typically start at 50 mg/day and gradually increase by 50 mg a month up to 200 mg, with the total daily amount divided into two equal doses. Birth control pills are often prescribed at the same time to counteract the irregular menstrual periods that spironolactone is known to cause. Treatment lasts for at least six months.(15, 30)
Iron may be a recommended supplement to take with spironolactone. In one small clinical study involving androgenetic hair loss, over 50% of participants treated with both iron and spironolactone had reduced hair loss.(50)
Potential Side Effects and Safety Precautions with Spironolactone
Women of child-bearing age should not take spironolactone without birth control pills because it can feminize a male fetus. Because of the risk of birth defect, it is considered a category X drug for pregnancy. This means it should absolutely not be taken by women who are pregnant or who think they might be pregnant.(15, 30)
Other adverse side effects can include:(15, 30)
- Breast tenderness
- Decreased libido
- Hypotension
- Increase in breast size
- Itchy skin
- Liver dysfunction
- Melasma-type hyperpigmentation of the skin
- Nausea
- Skin rash
Some experts consider spironolactone the safest systemic drug to use in treating FPHL. For those women who are also experiencing hirsutism due to conditions that promote excess androgen hormones, it is currently considered the gold standard in treatment. However, some studies suggest flutamide may be more effective.(15, 30, 203)
