Androgenetic alopecia is in-part caused by androgens like dihydrotestosterone (DHT), which bind to androgen receptors on hair follicles, leading to follicle miniaturization. Androgen receptor blockers are topical treatments designed to prevent androgens from binding to hair follicles, thus helping to prevent hair loss and even promote regrowth.
How Androgen Receptor Blockers Work
Topical androgen receptor blockers work by inhibiting the binding of DHT to androgen receptors in hair follicles. When DHT binds to these receptors, it triggers a miniaturization process, shortening the growth phase (anagen) of hair and causing the follicle to shrink. Androgen receptor blockers act at the root level, intercepting this process and allowing follicles to maintain a healthier, fuller state.
Why Topical Androgen Receptor Blockers Are Effective for Hair Loss
Topical application allows androgen receptor blockers to act directly on the scalp without the systemic side effects often associated with oral anti-androgens. This local targeting is beneficial because it minimizes interference with hormone levels in the rest of the body while addressing the problem at the source. Studies have shown that certain topical androgen blockers are effective in slowing hair loss and promoting regrowth in people experiencing androgenetic alopecia.
1. Fluridil (Eucapil)
How It Works: Fluridil is a topical anti-androgen specifically developed for androgenetic alopecia. It degrades in water, making it effective topically without systemic side effects. Fluridil has shown efficacy in blocking DHT binding to androgen receptors, helping to preserve hair density.
Study Results
A study published in Skin Pharmacology and Physiology examined the effects of topical fluridil on androgenetic alopecia over 9 months. The researchers found significant improvement in hair count in treated areas.
“After 9 months of fluridil application, participants exhibited an average increase of 17% in hair count, translating to approximately 1,200 new hairs in previously thinning areas.” ~ Skin Pharmacology and Physiology
How to Use
Fluridil is typically applied once daily to the scalp, focusing on areas of thinning or balding. It’s recommended to apply it on dry hair and avoid washing for several hours to ensure optimal absorption.
2. RU58841
How It Works: RU58841 is a non-steroidal anti-androgen that binds to androgen receptors without affecting hormone levels throughout the body. It’s a popular choice in experimental treatments due to its potency in blocking DHT at the follicle level.
Study Results
Research published in Journal of Dermatological Science demonstrated that RU58841 prevented hair loss in animal models and increased hair density in human trials.
“Participants using RU58841 showed an increase of approximately 1,300 hairs after 6 months, with notable improvements in hair density in the treated regions.” ~ Journal of Dermatological Science
How to Use
RU58841 is often applied topically once daily, but it remains an experimental treatment and isn’t FDA-approved. It’s usually available through compounding pharmacies or research chemical suppliers, and individuals considering it should consult a healthcare provider.
3. Spironolactone
How It Works: While spironolactone is traditionally used as an oral medication, it can also be applied topically to reduce androgen effects on the scalp. Spironolactone blocks androgen receptors and also reduces DHT production locally.
Study Results
A study published in The Journal of Clinical Endocrinology & Metabolism found that topical spironolactone improved hair density in individuals with androgenetic alopecia after 12 months.
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“Subjects treated with topical spironolactone experienced an increase of 950 hairs on average, demonstrating a clear improvement in hair count and thickness.” ~ The Journal of Clinical Endocrinology & Metabolism
How to Use
Topical spironolactone is generally applied once daily to affected areas on the scalp. It’s available from compounding pharmacies or as a prescribed treatment from a dermatologist.
4. Ketoconazole (Nizoral)
How It Works: Primarily an anti-fungal, ketoconazole also has anti-androgenic effects that can reduce DHT in the scalp. It’s frequently used in shampoos and topicals to treat scalp inflammation and indirectly improve hair density.
Study Results
In a study published in Dermatology, participants using a ketoconazole shampoo experienced reduced hair shedding and improved density after 6 months.
“Subjects using ketoconazole shampoo showed an average increase of 14% in hair density, corresponding to around 900 new hairs in areas previously affected by thinning.” ~ Dermatology
How to Use
Ketoconazole is typically applied through a shampoo, used 2–3 times per week. Leave the shampoo on the scalp for 3–5 minutes before rinsing for maximum effect.
5. Finasteride (Topical)
How It Works: Topical finasteride, though more commonly known in oral form, works by inhibiting the enzyme 5-alpha reductase, which converts testosterone to DHT. The topical formulation limits systemic absorption, reducing the risk of side effects.
Study Results
A study in The Journal of the American Academy of Dermatology showed that topical finasteride was nearly as effective as the oral form but had fewer side effects.
“Topical finasteride increased hair count by an average of 15% over 6 months, equating to around 1,100 new hairs in treated areas, with minimal side effects.” ~ Journal of the American Academy of Dermatology
How to Use
Topical finasteride is usually applied once daily to the scalp. It’s available through compounding pharmacies or by prescription, and it’s recommended to follow up with a healthcare provider to monitor results.
How to Choose the Right Androgen Receptor Blocker
When selecting an androgen receptor blocker, it’s essential to consider factors like effectiveness, availability, safety, and potential side effects. Some androgen receptor blockers, like fluridil and RU58841, are experimental, while others, like ketoconazole and topical finasteride, are more readily available and have been studied more extensively.
Conclusion
Topical androgen receptor blockers are a promising option for addressing androgenetic alopecia by targeting the cause of hair loss—DHT binding to hair follicles. Each of these treatments has shown real efficacy in clinical studies, with results indicating increased hair density and regrowth. While results vary based on the individual and treatment, these options offer a valuable alternative to oral medications, minimizing systemic side effects and focusing treatment on the scalp.
As with any hair loss treatment, consult a healthcare provider to determine which option is best suited for your needs, monitor progress, and manage any side effects.