[en] The origin of post-zosterian pain appears to be multiple. It implies: neuronal lesions in the central and peripheral nervous system. Young patients are less often affected than older individuals, perhaps because of damages that are caused or not to central afferences. Pain could be due to a central hyperexcitability induced and maintained by nociceptors. Antagonists of the NMDA receptor could thus prove efficient against installation of the chronic pain by interfering with neuronal discharges of the peripheral nociceptors and the induction of a hyperexcitability.