Topical insulin shows promising results for refractory neurotrophic keratitis

Topical insulin at a concentration of 10 IU/mL showed high healing rates, improved vision, and no complications in patients with refractory neurotrophic keratitis (NK) who failed standard treatments, according to a study.

The study evaluated 16 eyes from 15 patients with stage 2 or 3 NK who were unresponsive to conventional therapies. Participants applied topical insulin drops 6 times daily, alongside prophylactic fluoroquinolone drops. Treatment continued until the persistent NK healed, with regular anterior segment imaging.

Patients began the study with poor vision, averaging 1.7 logMAR. Following treatment, 75% experienced improved visual acuity, gaining an average of 0.5 logMAR. Corneal ulcers healed in a mean of 12.3 days, and the overall healing rate reached 93.75%. No complications or side effects were observed.

According to the authors, previous studies have examined topical insulin at various concentrations, but this is the first to use 10 IU/mL. The findings indicate that topical insulin may be a highly effective, accessible, and low-cost therapy for refractory NK. The researchers note that larger studies are needed to confirm the optimal concentration and to explore its role in treating other causes of refractory corneal ulcers.

Reference

Ben Addou Idrissi S, Filali Sadouk M, et al. Role of topical insulin in the management of resistant neurotrophic corneal ulcers. J Fr Ophtalmol. 2025;49(1):104709. doi: 10.1016/j.jfo.2025.104709. Epub ahead of print. PMID: 41364970.