I. Introduction
Androgenetic alopecia (AGA) is a common type of hair loss among European men. Traditional treatments mainly involve oral finasteride and topical minoxidil. However, oral medications carry the risk of systemic side effects such as sexual dysfunction. In recent years, topical finasteride preparations have become a research focus as they reduce systemic exposure by administering a high – concentration locally. This article summarizes its efficacy and safety based on European clinical research data.
II. Clinical Research Progress
1. Results of Phase III Clinical Trials (European Multicenter Study)
- Research Design: In 2021, a randomized, double – blind, placebo – controlled Phase III clinical trial was conducted in 45 research centers across Europe. 458 adult male AGA patients were enrolled to evaluate the efficacy and safety of topical finasteride.
- Main Efficacy: At 24 weeks, the target area hair count (TAHC) in the topical finasteride group increased by 20.2 hairs compared to the baseline, which was significantly better than the placebo group (6.7 hairs, P < 0.001). The efficacy was similar to that of oral finasteride (20.6 hairs). Statistical differences became apparent at 12 weeks of treatment.
- Mechanism of Action: Topical finasteride inhibits the activity of 5α – reductase in the local scalp, reducing the production of dihydrotestosterone (DHT). Its systemic exposure is only 1/100 of that of oral administration, and the decrease in serum DHT concentration is relatively small (34.5% vs. 55.6% for oral administration), theoretically reducing the risk of systemic side effects.
2. Support from Real – World Data
- Effect of Combination Therapy: A retrospective analysis of a German telemedicine platform showed that after 6 weeks of combined treatment with topical finasteride/minoxidil, 62.2% of patients had an improved hair appearance and 44.1% had an enhanced self – esteem. However, the incidence of local side effects (such as itching and erythema) was 11.8%, and there was no significant difference in sexual side effects compared with the oral group.
- Optimization of Carrier Technology: Research indicates that chitosan carriers can promote the penetration of finasteride. The amount of finasteride accumulated in the skin within 6 hours is 1 – 5 times that of a normal alcohol/propylene glycol solution. However, the difference in long – term effects diminishes. This suggests that different dosage forms may affect efficacy, but there is limited clinical comparative data.
III. Safety Analysis
1. Local Reactions
Mild to moderate skin irritation is common (itching 2.2%, erythema 2.2%). Most cases are tolerable, and the incidence of severe skin irritation is less than 1%.
2. Systemic Side Effects
Due to the extremely low systemic exposure, the incidence of sex – related side effects (such as decreased libido) is significantly lower than that of the oral group (0.6% vs. 4.8%), and there is no statistical difference compared with the placebo.
3. Contraindications and Precautions
It is contraindicated for pregnant and breastfeeding women. Avoid contact with mucous membranes. Long – term safety requires further observation.
IV. Usage Recommendations
1. Target Population
Mild to moderate male AGA patients with non – completely closed hair follicles.
2. Usage and Treatment Course
Apply topically once a day. Evaluate the efficacy after 3 – 6 months of continuous use. Long – term maintenance treatment is required.
3. Combination Therapy
It can be used in combination with minoxidil.
4. Monitoring and Adjustment
Follow – up regularly during treatment. If there is no effect after 3 months or severe side effects occur (such as persistent rashes), stop using the drug and seek medical advice.
V. Conclusion
European clinical studies suggest that topical finasteride spray has comparable efficacy to oral preparations in improving hair count, but with significantly fewer systemic side effects. It is especially suitable for patients sensitive to oral medications. Its chitosan carrier technology has enhanced transdermal absorption efficiency, but the differences in the effects of different dosage forms need further verification. Patients should use it under the guidance of a doctor to balance efficacy and safety.分享