I've had both. Ivig didn't help and second time I had it, I got aseptic meningitis. Plasmapheresis helped a lot.

I have had many, many periodic series of treatments, but do best with a regular schedule. I now get one treatment every other week.

With Ivig you can usually just get it in a vein. If you have really good veins, you can get plasmapheresis through the large veins in the crook of the elbow, one needle in each arm, but you have to lay very still during the treatment. One draws the blood out and the other returns it. My veins are too mushy and collapse, so I have to have a dual port.