Drug-induced scarring and permanent alopecia

Permanent drug-induced alopecia is uncommon but increasingly reported, with noninflammatory types linked to chemotherapy drugs like taxanes and busulfan, and hedgehog pathway inhibitors, while inflammatory types are associated with tyrosine kinase inhibitors and monoclonal antibodies, causing conditions like folliculitis decalvans and lichen planopilaris. The evidence is mainly from case reports, lacking robust pathology or long-term studies. This review aims to update on drugs causing scarring or permanent alopecia, detailing their prevalence, clinical features, and management strategies.