for such purposes is unethical. Bicalutamide, a pure androgen receptor antagonist with the same mechanism as flutamide and with comparable or superior antiandrogenic efficacy but with a far lower risk of liver toxicity, is an alternative option to flutamide in the treatment of androgen-dependent skin and hair conditions in women. Clascoterone is a topical antiandrogen that has demonstrated effectiveness in the treatment of acne in both males and females and was approved for clinical use for this indication in August 2020. It has shown no systemic absorption or associated antiandrogenic side effects. In a small direct head-to-head comparison, clascoterone showed greater effectiveness than topical isotretinoin. 5α-Reductase inhibitors such as finasteride and dutasteride may be useful for the treatment of acne in both males and females but have not been adequately evaluated for this purpose. Moreover, 5α-reductase inhibitors have a strong potential for producing birth defects in male babies and this limits their use in women. However, 5α-reductase inhibitors are frequently used to treat excessive facial/body hair in women and can be combined with birth control pills to prevent pregnancy. There is no evidence as of 2010 to support the use of cimetidine or ketoconazole in the treatment of acne. Hormonal treatments for acne such as combined birth control pills and antiandrogens may be considered first-line therapy for acne under many circumstances, including desired contraception, known or suspected hyperandrogenism, acne during adulthood, acne that flares premenstrually, and when symptoms of significant sebum production (seborrhea) are co-present. Hormone therapy is effective for acne both in women with hyperandrogenism and in women with normal androgen levels. Azelaic acid Azelaic acid is effective for mild to moderate acne when applied topically at a 15–20% concentration. Treatment twice daily for six months is necessary, and is as effective as topical benzoyl peroxide 5%, isotretinoin 0.05%, and erythromycin 2%. Azelaic acid is an effective acne treatment due to its ability to reduce skin cell accumulation in the follicle and its antibacterial and anti-inflammatory properties. It has a slight skin-lightening effect due to its ability to inhibit melanin synthesis. Therefore, it is useful in treating individuals with acne who are also affected by post-inflammatory hyperpigmentation. Azelaic acid may cause skin irritation. It is less effective and more expensive than retinoids. Azelaic acid also led to worse treatment response when compared to benzoyl peroxide. When compared to tretinoin, azelaic acid makes little or no treatment response. Salicylic acid