Chinese herbal medicine for treatment of diabetic peripheral neuropathy

Diabetic peripheral neuropathy (DPN) is one of the most common complications of diabetes. It is characterized by a progressive loss of nerve fibres that predisposes the person to painful or insensitive extremities, ulceration and amputation, and results in a large disease burden in terms of incapacity for work, quality of life and use of healthcare resources. This systematic review identified a total of 39 trials that included 2890 participants with DPN. We evaluated the effects of various herbal formulations (including single herbs, Chinese proprietary medicines, and mixtures of different herbs) for treating people with DPN. All the identified clinical trials were performed and published in China. There was inadequate reporting on adverse events in the included trials. Most of the trials did not mention whether they monitored for adverse effects. Only two trials reported adverse events but one occurred in the control group in one trial and it was unclear in which group they occurred in the other trial. Conclusions about the safety of herbal medicines cannot therefore be drawn from this review due to inadequate reporting. Most of the trials were of low methodological quality and the interpretation of any positive findings for the efficacy of the included Chinese herbal medicines for treating DPN should be made with caution. Based on this systematic review, there is no evidence to support the objective effectiveness and safety of Chinese herbal medicines for DPN. No well designed, randomized placebo controlled trial with objective outcome measures has been conducted.