Oral Ketamine Administration in Patients With Peripheral Neuropathic Pain

In previous studies, it was shown that when ketamine was administrated by the intravenous route, its analgesic action was rapid. In one study, when oral ketamine was administrated to patients suffering from neuropathic pain, in six out of nine patients, pain was relieved after 24 hours post-administration. In this study, ketamine will be administrated during seven days, which will allow us to evaluate ketamine efficiency and safety. The effect of ketamine on pain intensity will be mainly studied using a visual analogue scale (VAS) but also taking into account the score assigned by the patient to his pain. This score will be noted down by patients before, during and after ketamine treatment. Evaluation of benefit/risk for ketamine administration during this trial, shows that even if adverse events are not excluded, the benefit for the patients may be neuropathic pain relief. Because clinical current knowledge regarding oral administration of ketamine is limited, this trial intends to enlarge information about ketamine efficiency and safety, more particularly in neuropathic pain disorders.