Today, about 50% of men and 15–30% of women suffer from hair loss as well as the associated psychological impact. Drug therapy, especially through topical administration, is the main treatment strategy for stimulating hair regrowth. However, challenges exist due to the skin barrier that hinders drug penetration. To this end, many efforts have been made to enhance drug penetration efficiency. This review focuses on the advancement of the transdermal drug delivery strategies for hair loss therapy reported in the last five years, especially those via nanoformulations for topical administration and microneedles for transdermal delivery. In addition, physical or chemical penetration enhancers are also introduced, which are often applied with the drug delivery systems to achieve a synergy effect.

中文翻译：

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用于头发再生的透皮给药

今天，大约 50% 的男性和 15-30% 的女性患有脱发以及相关的心理影响。药物治疗，特别是通过局部给药，是刺激头发再生的主要治疗策略。然而，由于阻碍药物渗透的皮肤屏障，存在挑战。为此，已经做出许多努力来提高药物渗透效率。本综述重点介绍了过去五年中报道的用于脱发治疗的透皮给药策略的进展，尤其是通过用于局部给药的纳米制剂和用于透皮给药的微针。此外，还引入了物理或化学渗透促进剂，通常与药物递送系统一起应用以达到协同作用。