Nerve Regeneration in Neuropathic Pain

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With great interest we noticed the analgesic effect of palmitoylethanolamide (PEA) in pudendal neuralgia, as described in a recent case report [1]. Recently, at ...
Pain Medicine 2010; 11: 1576 Wiley Periodicals, Inc.

LETTER TO EDITOR Nerve Regeneration in Neuropathic Pain

With great interest we noticed the analgesic effect of palmitoylethanolamide (PEA) in pudendal neuralgia, as described in a recent case report [1]. Recently, at the Third International Congress on Neuropathic Pain (NP), the group of Biasiotta presented new data in 30 neuropathic pain patients treated with PEA [2]. NP, positive sensory symptoms, and amplitudes of the action potentials measured by laser-evoked potentials improved significantly. These findings might point to nerve regenerating properties of PEA, and therefore deserve more attention. Various supplements demonstrated nerve generative properties, as has been shown in animal models [3]. Acetyl-L-carnitine can be seen as a prototype of the class of rational supplements. This drug significantly increased the number of fibers and regenerating clusters in patients suffering from NP in diabetes [4]. Alpha-lipoic acid has comparable nerve regenerating properties, as has been demonstrated via nerve conduction velocity studies [5]. Sadly enough, supplements such as PEA do not receive adequate attention of the research community due to the fact that these molecules are not patent protected. Even positive results of meta-analysis and well-randomized controlled trials are not implemented by the prescribing physicians, neither are these results part of modern treatment guidelines [6,7]. In our institute, we also regularly see clinically relevant analgesic responses in otherwise treatment refractory NP patients, after adding the aforementioned supplements to a regular treatment regimen. Hopefully, with the emerging recognition of the relevance of multimodal therapies for NP, rational supplements will be taken into account. DAVID J. KOPSKY, MD,* and JAN M. KEPPEL HESSELINK, MD, PhD† *Director Clinical Operations † Director Research and Development Institute for Neuropathic Pain Soest, the Netherlands

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