What is causing the numbness in my toes?

Question:
I started Aubagio two months ago and before that I was using Avonex. I have also started to walk for about 45 minutes a day. I feel kind of numbness at my left side toes. Is this related to exercise? Just MS? Is Aubagio as effective as Avonex? 

Answer:
Anytime you have new symptoms that are concerning, please check with your clinician. In general symptoms can be a sign of a new exacerbation OR they can come and go based on prior damage that has occurred. Sometimes, symptoms such as numbness are related to things other than MS. In most instances, the symptoms are NOT a sign of new inflammation, but your clinician can guide you on whether testing will be required. In terms of comparing Aubagio and Avonex we have limited data. At a population level they are probably equivalent, but there will be some people who respond to one drug and not the other. Careful follow up is needed on any disease modifying therapy to determine if it is working for you.

Benjamin M. Greenberg, MD, MHS
Director, Transverse Myelitis, Neuromyelitis Optica Programs
Director, Neurosciences Clinical Research Center
Co-Director, Pediatric CONQUER Program
UT Southwestern Medical Center
Childrens Health
Dallas, Texas