Also, does it work for small fiber neuropathy?

IVIG works for SFN when it is caused by an autoimmune disorder

As far as I know, for most insurance to approve IVIG, you must qualify by having diagnosed neuropathy due to a proven autoimmune disease. They tried for me and although I have a very high ANA, they can't find the name for it so I can't get it.

Usually you do need to have a documented autoimmune disease, but not always.

I was recently chatting with a person who had significant SFN in his legs that was caused by Lyme. He has not been diagnosed with any autoimmune diseases. But he sought out a doctor who was brilliant and well known for getting IVIG approved. So, the IVIG was approved and his insurance totally covered it. He was on it for 8 months. Unfortunately it didn't help him at all. And his legs still burn so badly that he can't even tolerate wearing pants.