A retrospective cohort study of the efficacy of metronidazole in oral lichen planus

Lichen planus (LP) is an inflammatory dermatosis with mucosal variants, including oral LP (OLP). OLP has a relapsing chronic course and may significantly affect a patient's quality of life. We analysed the efficacy of metronidazole as a treatment for OLP via a retrospective chart review of patients with a diagnosis of OLP seen at our institution over 10 years. Thirty patients with OLP were treated with metronidazole 500 mg twice daily. Most patients (n = 18; 60%) showed improvement with metronidazole, including 10 (33%) who experienced complete resolution of symptoms. Our results were limited by the retrospective nature of the review and the relatively small cohort size. Given the efficacy, mild side-effect profile and the less immunosuppressive nature of metronidazole vs. alternative systemic treatment options, metronidazole is a reasonable option to try in patients with symptomatic OLP who have failed topical treatment options. Oral lichen planus (OLP) may significantly affect a patient's quality of life. We aimed to analyse the efficacy of metronidazole as a treatment for OLP. We reviewed patients with OLP at our institution over 10 years. Thirty patients with OLP were treated with metronidazole 500 mg twice daily and most (n = 18; 60%) showed improvement, including 33% with eventual complete resolution of symptoms. Our results were limited by the retrospective nature of the study, but given the efficacy, mild side-effects and milder immunosuppression vs. other treatment options, metronidazole is a reasonable option to try in patients with symptomatic OLP who have failed topical therapies.