Low-Dose Naltrexone Use in Biopsy-Proven Lichen Planus of the Nails.

Importance: Nail lichen planus has the potential to cause permanent destruction of the nail unit and remains challenging to treat. Studies suggest that low-dose naltrexone is a safe and potentially effective treatment for other dermatologic conditions, including lichen planopilaris.

Objective: To assess the effectiveness of low-dose naltrexone in treating nail lichen planus.

Design, setting, and participants: This case series evaluates 7 adult patients with biopsy-proven nail lichen planus who were treated with low-dose naltrexone (3 mg per day) at the University of Miami dermatologic clinics from November 2022 to December 2023. The data were analyzed in March 2024. Patients were treated for at least 2 months and had in-person follow-up evaluation while receiving treatment.

Main outcomes and measures: The main outcome was posttreatment clinical nail lichen planus severity index, which was scored as clear, mild, moderate, or severe. Patients were evaluated for oral and cutaneous disease during the course of treatment. Tolerance and adverse events were noted.

Results: A total of 7 patients (mean [range] age, 60 [38-77] years; 3 female individuals) were included. All but 1 patient had been previously treated and did not respond to at least 1 prior treatment (median [range], 2.5 [0-4.0] treatments). Treatment duration ranged from 2 to 11 months. Clinical response was observed in 4 of 7 patients, with an overall 35% reduction in nail lichen planus severity index. Two patients with severe disease achieved a reduction to mild severity. None of the patients had to discontinue low-dose naltrexone due to adverse events, and no adverse events were reported.

Conclusions and relevance: The results of this study suggest that low-dose naltrexone may be a therapeutic approach for treating nail lichen planus. Further controlled studies are warranted to better understand its clinical efficacy and safety profile in treating nail lichen planus.