The Effect of Oral Verapamil on the Visual Evoked Potentials in Definite Multiple Sclerosis Patients

Introduction: Ionic channel rearrangements through the demyelinated axons or supporting media play significant role in remission of the neurological deficit in MS patients. In this study the effects of Verapamil as a calcium channel blocker on central conduction have been investigated through the evaluation of changes in P۱۰۰ latency of the visual evoked potential. Method: This randomized double blinded, placebo-controlled, clinical trial was performed on two groups of ۲۰ multiple sclerosis patients who had been diagnosed for definite MS and had no relapse during the last year. Case group received oral Verapamil, ۴۰ mg, every ۸ hours and was compared to Placebo group for changes in P۱۰۰ latency. Results: In the Verapamil group, the P۱۰۰ latencies showed an average decrease of ۵ms comparing to the placebo group (۶.۱±۴ms vs۱ ± ۰.۵ ms). Verapamil had no significant effect on the VEP duration. Discussion: The present study suggests that pharmacological manipulation of calcium-dependent process, possibly at the level of demyelinated axon, can acutely facilitate central conduction of electrical impulses in some patients with clinically stable multiple sclerosis.