Biotin in high doses was given for 1-2 years to three diabetic patients suffering from severe diabetic peripheral neuropathy. Within 4-8 weeks there was a marked improvement in clinical and laboratory findings. It is suggested that in diabetes may exist a deficiency, inactivity or unavailability of Biotin, resulting in disordered activity of biotin-dependent enzyme, pyruvate carboxylase, leading to accumulation of pyruvate and/or depletion of aspartate, both of which play a significant role in nervous system metabolism. Based on our good results, regular biotin administration could be suggested for every diabetic patient for the prevention and management of peripheral neuropathy although extensive randomised clinical trials are required.