Dalfampridine is associated with de novo occurrence or reoccurrence of positive sensory symptoms in MS.

Abstract

INTRODUTION Oral extended release dalfampridine (FA) is a recently approved medication that blocks voltagedependent potassium channels inhibiting functioning of axonal membranes. It results in improved conduction affecting ambulation in a subgroup of patients with multiple sclerosis (MS) 1-2 Paroxysmal symptoms are due to abnormal electrical discharges due to demyelinated nerve fibers and include sensory paroxysms such trigeminal neuropathy associated with MS (TN) and motor paroxysms such as painful tonic spasms. These symptoms are present in approximately 10 percent of subjects with MS 3 . The hypothesis is that if FA enhances sensory fiber conduction it may simultaneously incite action potential conduction in damaged sensory nerves, resulting in new positive sensory symptoms such as parasthesia or pain.