I would highly recommend taking pre-meds of Tylenol and Benadryl, prior to your treatment. For one thing, Benadryl makes me sleepy so I sleep through some of the IVIG!:D
I take benadryl at home — much cheaper than what the hospital charges and it has a longer time to get into my system. In my earlier treatments, they would pre-medicate with solumedrol, which, to me, did nothing but extend the treatment session and make my blood sugar go sky high.
If nothing else, tylenol and benadryl will keep your comfortable.:)