Perforating foot ulcers constitute a major problem in diabetics with peripheral neuropathy for which no specific therapy is available. Twenty patients with chronic, resistant mal perforant were treated by local application of dimethylsulfoxide (DMSO) solution. Complete healing of the ulcers was achieved in 14 patients following 4–15 weeks of daily treatment. Partial resolution was observed in another four patients, and in the remaining two there was no effect. A control group, equal in number, was treated conventionally. Complete healing of the ulcers took place in only two patients. The therapeutic effect of DMSO most probably results from an increase in tissue oxygen saturation via a combined mechanism of local vasodilatation, decreased thrombocyte aggregation, and increased oxygen diffusion. Local DMSO is effective, simple, devoid of systemic side effects, and inexpensive. It should be employed for diabetic foot ulcers prior to the consideration of surgical measures.J Am Geriatr Soc 33:41, 19