Multiple sclerosis (MS) is the most common cause of neurological disability in young adults. Recent studies have implicated specific sodium channel isoforms as having an important role in several aspects of the pathophysiology of MS, including the restoration of impulse conduction after demyelination, axonal degeneration and the mistuning of Purkinje neurons that leads to cerebellar dysfunction. By manipulating the activity of these channels or their expression, it might be possible to develop new therapeutic approaches that will prevent or limit disability in MS.