Intralesional Methotrexate Beneficial in Plantar Warts

Plantar warts may be treated efficaciously and safely with an intralesional injection of methotrexate 25mg/mL once every 2 weeks for up to 6 sessions, according to study findings published in Dermatologic Therapy.

Researchers sought to assess the efficacy and safety of methotrexate 25mg/mL in treating plantar warts.

They conducted a prospective, open-label pilot study that included 20 patients (mean age, 28.45±8.66 years, range 18-46 years; 10 women) who received intralesional methotrexate 25mg/mL every 2 weeks until complete clearance, with treatment maximum of 6 sessions.

Patients had warts for 4 to 18 months (8.05±3.25 months); 14 patients had 1 or 2 warts, 5 patients had 3 warts, and 1 patient had 4 warts.

Researchers reported no clearance prior to 4 sessions. After 4 sessions, they observed complete clearance in 2 patients and no clearance in 18 patients. After 5 sessions, they noted complete clearance in 6 patients (including the 2 previously reported) and no clearance in 14 patients. After 6 sessions, they found complete clearance in 1 additional patient (total cleared after 6 sessions=7), no clearance in 5 patients, and partial clearance in the remaining 8 patients. Before this session, no partial clearance had been observed.

No side effects were reported by 9 patients and the remaining 11 patients reported pain (8) and bruises (6). Overall, there was a better response in patients with fewer warts assessed by complete/partial response after 6 sessions as patients with 1 wart showed 85.72% response rate, those with 2 warts, 71.43%, and patients with 3 warts, 80.00%. The patient with 4 warts did not respond at all. This did not represent a statistically significant correlation between the response rate and the number of warts, it was noted.

Researchers concluded that intralesional methotrexate is minimally invasive, inexpensive, and results in acceptable cosmetic outcomes. Side effects are minor, mostly related to injection pain, and compared with oral therapy, it reaches a higher drug concentration locally within the lesion. Researchers said “The findings of the current study suggest that biweekly sessions of full (25 mg/mL) concentration of methotrexate are a safe and effective treatment for plantar warts.” They added “It may be considered an alternative line of treatment in cases of resistant plantar warts.”

Reference

Zoheir MGT, Almohsen AM, Amer MAEM, Abdel-Hameed AKS. Intralesional full-concentration (25 mg/ml) methotrexate in the treatment of plantar warts: a pilot study. Dermatol Ther. Published online September 13, 2022. doi:10.1111/dth.15815