What does finasteride do to the female body? Find out its side effects.

Finasteride is a drug primarily used in men to treat hair loss and prostate problems. However, when a woman takes it, it can have unexpected and potentially harmful effects on her body. Here we explain, in simple terms, what scientific studies say about it.

What is Female Pattern Hair Loss (FPHL)?

FPHL (Female Pattern Hair Loss) is a common condition that affects many women and is characterized by a gradual thinning of hair, usually at the top of the head, particularly along the parting line. Unlike male pattern baldness, which often results in receding hairlines or bald spots, FPHL leads to overall hair thinning. This condition is mainly linked to hormonal and genetic factors. One key cause is an imbalance in androgens (male hormones), which can lead to the miniaturization of hair follicles, making hair thinner and weaker. FPHL usually starts around the age of 40, although it can appear earlier due to factors like hormonal changes, stress, or genetics.

What is the difference between DHT and FPHL?

Dihydrotestosterone (DHT) is an androgen (male hormone) derived from testosterone. It plays a significant role in hair loss by shrinking hair follicles over time, making hair thinner and weaker. In men, high levels of DHT are strongly linked to male pattern baldness. In women, the relationship between DHT and hair loss is more complex. While some cases of FPHL involve increased DHT sensitivity, not all women with FPHL have high DHT levels. Instead, FPHL is often influenced by a combination of genetics, hormonal fluctuations, and aging. This difference is why treatments like finasteride, which reduce DHT, may not be as effective for female hair loss as they are for men.

Is finasteride effective and safe for women?

Finasteride works by blocking an enzyme called 5-alpha reductase, which converts testosterone into a stronger form called dihydrotestosterone (DHT). In men, reducing DHT slows hair loss and helps with prostate health. However, in women, its effects are more controversial and potentially dangerous.A study published in The Journal of Clinical Endocrinology & Metabolism found that some women with FPHL saw improvement in hair growth after taking finasteride at doses between 1 and 5 mg daily. However, the response varies from person to person, and the drug is not FDA-approved for hair loss treatment in women due to potential risks. Additionally, a review in The Journal of the American Academy of Dermatology warns that there is insufficient evidence to support its widespread use in women and that long-term safety remains uncertain

What are the risks and side effects of finasteride in women?**

While some women have experienced hair growth with finasteride, the drug can also cause severe hormonal changes, leading to:

• Irregular menstrual cycles
• Decreased libido
• Fatigue
• Mood changes, including depression and anxiety
• Increased risk of breast tenderness and possible hormone-related complications

A systematic review in The International Journal of Trichology noted that women taking finasteride frequently reported these side effects, likely due to alterations in androgen levels. Moreover, research in The Journal of Clinical Pharmacology highlighted cases where finasteride use in women led to persistent side effects even after stopping the drug.

Can finasteride cause problems during pregnancy?

One of the biggest concerns with finasteride use in women is its potential to cause birth defects. A study in PubMed highlights that if a pregnant woman takes finasteride—or even comes into contact with crushed pills—the drug can interfere with fetal development, particularly affecting the genitals of male fetuses. Because of this risk, women who are pregnant or may become pregnant should avoid finasteride completely. The FDA has classified finasteride as a Category X drug, meaning it is contraindicated for use in pregnancy due to its high teratogenic potential.

Why finasteride is not recommended for women...

In general, finasteride is not considered safe for women. While some studies report hair growth benefits, the risks, including hormonal imbalances, potential irreversible side effects, and pregnancy-related dangers, outweigh the benefits. A 2023 review in The European Journal of Dermatology concluded that alternative treatments such as minoxidil, low-level laser therapy, platelet-rich plasma (PRP), and hormonal therapies under medical supervision are safer and more effective options for female hair loss.

Conclusion: Should women take finasteride?

Although finasteride has shown some effectiveness in certain women with hair loss, its risks far outweigh the potential benefits. The hormonal side effects, dangers during pregnancy, and lack of FDA approval make it an unsuitable choice for most women. Those experiencing hair loss should consult a healthcare professional to explore safer alternatives, such as minoxidil, PRP therapy, or other hormone-regulating treatments tailored to female physiology.

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Sources:

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