What is Flutamide?

• Does Flutamide Regrow Hair?
• Flutamide Dosing
• Flutamide Side Effects and Safety

Flutamide is an oral nonsteroidal anti-androgen drug used as an off-label treatment for women with female pattern hair loss (FPHL). Like other androgen receptor antagonist drugs, it blocks DHT from attaching to hormone receptors at hair follicles. This prevents DHT from triggering cellular and genetic activity that leads to hair loss.^(15, 203)

Can Flutamide Stop Hair Loss?

Clinical evidence of flutamide's effectiveness at treating FPHL is positive:

• In one clinical trial published in 2003, flutamide led to modest regrowth of hair in women with FPHL. The women also had higher-than-normal levels of androgen hormones.⁽¹⁵⁾
• Results of a lengthy clinical trial involving 4 years of flutamide treatment (with or without oral contraception) demonstrated significant improvement in hair loss. Patients showed an average of 15% improvement the first year, increasing to 28% by the end of the second year. Improvement remained stable for the final two years of the study. Interestingly, this study involved 101 women with FPHL with no symptoms or lab results indicating excess androgens (e.g., acne, hirsutism, Cushing disease, polycystic ovary syndrome).⁽¹⁰⁴⁾

Other experts, however, consider flutamide less effective than other anti-androgen drugs. They assert that flutamide is only as effective in cases of women experiencing hirsutism as well as hair loss. Concern over toxicity to the liver may also be a deterrent to using flutamide. However, results from the 4-year clinical trial suggests toxic effects on the liver are only found at high dosage levels.^(30, 104)

Dosing Information for Flutamide

In the 4-year prospective study, patients were started out with 250 mg/day of flutamide for the first year. The dose was decreased to 125 mg/day during the second year.⁽¹⁰⁴⁾

For the final 2 years of treatment 62.5 mg/day was taken. The researchers referred to this as a maintenance dose since maximum benefit was seen at the end of the first two years and maintained for the final two.⁽¹⁰⁴⁾

Because of concerns over toxic side effects, some experts recommend doses between 62.5 and 125 mg/day. An earlier study conducted in 1993 using doses of between 250-375 mg/day to treat hair loss in women with SAHA syndrome (characterized by excess androgen hormone secretion). These higher doses caused severe toxic effects in the liver for 13% of study participants.⁽³⁰⁾

Potential Side Effects and Safety Precautions with Flutamide

Women capable of conception should not take flutamide 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. That means it should absolutely not be taken by women who are pregnant or who think they might be pregnant.^{(15, 30, 104)}

At higher doses, flutamide can cause serious liver problems. In one study where doses of 250-375 mg/day were given, 13% of the women involved showed severe toxic effects in the liver (hepatotoxicity).^(30, 104)

However, a recently published long-term study showed only 4% of participants had to withdraw because of hepatotoxicity (as evidenced by high levels of liver enzymes). And although a significant number of participants did withdraw before completion of the full four years of this clinical study, most did so because the treatment was successful or other non-study related reasons.^(30, 104)

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