Resorcinol in Dermatology: Reassessing a Legacy Topical Therapy for Contemporary Clinical Use.

Resorcinol is a phenolic topical agent (Figure 1) with a long history in dermatology, but its role in contemporary practice has narrowed substantially. This review summarizes the mechanism, formulation considerations, clinical applications, safety profile, and future relevance of topical resorcinol. Resorcinol has keratolytic, antiseptic, antifungal, anti-inflammatory, and tyrosinase-inhibitory properties that support its use in acne, hidradenitis suppurativa, chemical peels, hyperkeratotic disorders, and pigmentary conditions. Despite historical use in acne, current evidence and guideline support are limited, and resorcinol remains largely absent from routine acne management. In contrast, topical resorcinol has a more defined role in mild to moderate hidradenitis suppurativa, particularly as a nonantibiotic option for localized inflammatory lesions. Safety concerns, especially thyroid toxicity, have contributed to its decline. However, reported systemic toxicity largely involved prolonged high-dose application to ulcerated or compromised skin, which differs from limited modern dermatologic use. Practical barriers, including lack of commercial availability at clinically relevant concentrations and dependence on compounding, also limit adoption. Resorcinol may be better viewed as an underused legacy compound rather than an obsolete therapy.