No, that is not a big dose. I think it's about equivalent to 5 mg of Prednisone.

It's a pretty standard low maintenance dose for regular use in autoimmune disease.

However, it is NOT a standard pre-med dose for IVIG. Most taking IVIG get one larger dose by IV just prior to infusion (along with benadryl and tylenol). I either receive 40 mg of medrol or 10 mg of dexamethasone IV. This was the standard dose even when I first started getting IVIG back in 1997 (for 9 years). Everyone in the infusion room got the same.

Since you got 30 days worth, it seems she wants you on it daily. Maybe she thinks in your case a steady dose will work better...for your flares.

Reactions to IVIG usually occur within the first 5 days. It would be quite rare to do fine the first week and then react after that, so I don't think the daily medrol is just for the IVIG. That being said, maybe a daily dose will just help you with 'flares' and keep your AI disease more stable. Maybe she will give you IV medrol also before your infusion.

Most common side effects are weight gain, bones loss, GI upset (take it with food to help this). I had problems with hot flashes from it. I had no idea it was the medicine until I researched. When I tapered off, the hot flashes tapered down too...and stopped after I stopped the steroid. However, I don't get the hot flashes with the large one time IV dose before my IVIG...hmm

I will add: If you take this for more then one week, then you MUST taper off it carefully to avoid withdraw syndrome.