multiple sclerosis
"I just had my 4th infusion.  Since the previous one and this past one, I have been extremely fatigued.  Can't seem to do anything for any period of time.  Have trouble sleeping due to a strange feeling I get in my chest (feels like my pulse is jumping out of my chest, no pain, just a very weird feeling).  I was hoping this Tysabri was going to help me, but it hasn't. :("