Frontal Alopecia After Repeated Botulinum Toxin Type A Injections for Forehead Wrinkles: An Underestimated Entity?

The document reports an observational study on 5 female patients who experienced frontal alopecia following repeated botulinum toxin type A (BTXA) injections for forehead wrinkles. The patients, with a mean age of 52.7 years, had been receiving BTXA injections at intervals ranging from 4 to 6 months. They all noticed a progressive recession of the hairline, with a mean distance of over 6 cm from the hairline to the glabella. Clinical and trichoscopic examinations revealed normal skin with signs of photoaging, no atrophy or scarring, and the presence of vellus and intermediate hair along the hairline. The study introduced the term 'botulin-induced frontal alopecia (BIFA)' to describe this phenomenon and differentiate it from other types of hair loss such as frontal fibrosing alopecia (FFA) and androgenetic alopecia. The authors suggest that dermatologists should be aware of the potential for frontal alopecia as a side effect of BTXA injections and call for further research to understand the prevalence and etiopathogenesis of BIFA.