The effect of topical phenytoin on healing in diabetic foot ulcers: a randomised controlled trial

Aim The aim of the study was to evaluate the effect of topical phenytoin on healing in diabetic foot ulcers. A randomized, controlled, double-blind, clinical trial was conducted.

Methods A phenytoin dressing and a control dressing were manufactured. Individuals who were ≥ 18 years of age with peripheral neuropathy, an ankle brachial pressure index > 0.5 and a diabetic foot ulcer ≥ 4 weeks’ duration were independently randomized to the phenytoin group (31 participants) or the control group (34 participants). Participants with renal disease, ankle brachial pressure index < 0.5, necrosis or osteomyelitis were excluded. Subjects received standard wound care and dressing application. Primary endpoint analysis (diabetic foot ulcer closed or not at 16 weeks) was calculated by survival analysis.

Results Participants (n = 65, 52 with Type 2 diabetes) were treated for a maximum of 16 weeks. Sixty per cent of the diabetic foot ulcers closed overall (18 in the phenytoin group, 20 in the control group) with no statistically significant differences in complete healing or in diabetic foot ulcer area over time between the two groups. At 24-weeks follow-up, one diabetic foot ulcer had recurred.

Conclusions There were no differences in diabetic foot ulcer closure rates or in diabetic foot ulcer area over time between the two groups. This study does not support the use of phenytoin in the treatment of diabetic foot ulcers.