This retrospective case series described the use of topical insulin drops as an aid in treatment of refractory neurotrophic corneal ulceration in six patients. Insulin drops were prepared under sterile conditions from standard insulin preparations mixed with artificial tears containing polyethylene glycol and propylene glycol at a concentration of 1 unit per millilitre. They were refrigerated and could be stored for up to one month from preparation. All six patients had non-healing epithelial defects in neurotrophic corneas, which failed to respond to standard medical therapies including: drops, amniotic membranes, temporary tarsorrhaphies. In all patients insulin drops were used between two to three times per day and continued beyond the resolution of epithelial defect. Complete re-epithelialisation was observed in all patients within seven to 25 days. The mechanism of topical insulin in promoting corneal healing is not fully understood, but insulin is thought to help restore corneal nerves plexuses and improve epithelial cell migration. Also insulin-like growth factor-1 is involved in corneal wound healing. Topical insulin may be simple treatment for refractory neurotrophic corneal ulcers, but further studies are needed. – MP