Evaluating Sativex® in Neuropathic Pain Management: A Clinical and Neurophysiological Assessment in Multiple Sclerosis.

OBJECTIVE: The aim of our study was to better investigate the role of Sativex(®) in improving pain in multiple sclerosis (MS) patients by means of either clinical or neurophysiological assessment.

SETTING: Pain is a common symptom of MS, affecting up to 70% of patients. Pain treatment is often unsatisfactory, although emerging drugs (including cannabinoids) are giving encouraging results. Clinical pain assessment in MS is very difficult, and more objective tools are necessary to better quantify this symptom and its potential response to the treatments.

SUBJECTS AND METHODS: We enrolled 20 MS patients (10 with and 10 without neuropathic pain), who underwent a specific clinical (such as visual analog scale) and neurophysiological assessment (by means of laser-evoked potentials and transcranial magnetic stimulation), before and after 4 weeks of Sativex administration.

RESULTS: One month of drug administration in MS patients with neuropathic pain successfully reduced pain rating and improved quality of life. Interestingly, such effects were paralleled by an increase of fronto-central γ-band oscillation and of pain-motor integration strength.

CONCLUSIONS: Our data suggest that Sativex may be effective in improving MS-related neuropathic pain, maybe through its action on specific cortical pathways.