Ketoconazole (topical)

Also known as: Nizoral (shampoo brand), azole antifungal

Hair RestoreDermatology

In plain English

Ketoconazole is an antifungal used on the skin and scalp. On the scalp it reduces yeast (Malassezia) and inflammation, which is why it treats dandruff and seborrheic dermatitis and is often added to hair-loss regimens as a supportive ingredient. On the skin it treats fungal rashes. Topical use is considered safe; the oral pill form is avoided for cosmetic uses because of liver risk.

The science

Ketoconazole inhibits fungal cytochrome P450 14-alpha-demethylase, blocking ergosterol synthesis in the fungal cell membrane, and has intrinsic anti-inflammatory and mild anti-androgenic activity in the skin. A small comparative study found 2% ketoconazole shampoo improved hair density, follicle size, and the proportion of anagen follicles comparably to 2% minoxidil, supporting an adjunctive role in androgenetic alopecia. A Cochrane review of seborrheic dermatitis found topical ketoconazole roughly 31% more likely to clear rash than placebo and as effective as topical steroids with fewer side effects.

References

• Pierard-Franchimont C et al., Dermatology 1998 (ketoconazole in androgenetic alopecia)
• Okokon EO et al., Cochrane Database Syst Rev 2015 (topical antifungals for seborrhoeic dermatitis)