The Efficacy of Topical Dapsone in Lichen Planopilaris with Beard Involvement: Potential Role for Neutrophil Involvement in Pathogenesis

Herein, we highlight the potential effectiveness of topical dapsone as an alternative treatment for lichen planopilaris (LPP), a lymphocytic scarring alopecia that occasionally involves the beard. A 44-year-old healthy man presented with progressive hair and beard loss accompanied by pigment darkening, and a biopsy confirmed LPP. Standard therapeutic options were initiated; however, hydroxychloroquine was discontinued due to a drug eruption, while intralesional corticosteroids and topical pimecrolimus were ceased due to clinical unresponsiveness. Subsequent systemic treatments, such as corticosteroids and methotrexate, were also halted because of elevated liver enzymes, leaving limited therapeutic choices. Initiation of topical 7.5% dapsone led to a rapid and substantial decline in disease activity within one month, followed by a sustained two-year remission without adverse effects. This notable response suggests that topical dapsone may be a valuable non-systemic option for LPP patients who cannot tolerate conventional therapies and supports the possible involvement of neutrophilic inflammation in disease pathogenesis.