of a person REALLYsweating BULLETS? They don't. They can't.
No where have I read of anyone sweating blood either.

Immune Globulins have a 'life span', just as red and white blood cells do.
Immune globulines are a blood component, and have life spans like that of blood cells. The good IG's do in any individual's system varies from person to person. One can require it every week, bi-weekly, monthly up to once a year.

As I understand it, all blood and blood products[parts] such as IVIG, leave your body through your renal system. Your docs will take blood tests to see if the ivig has changed certain numbers [as it should] and also to see if adding it has placed an undue strain on that renal system. The strain, should there be any, is because the IG's infused - are a foreign entity put into your system, and a lot have been added, meaning extra stress and strain for your body. Should there be too much stress, as shown by the blood tests, a risk assessment will be made and decisions about whether to continue will also be made. The symptoms of renal system failure are few, and should they appear it is usually too late. Therefore the blood tests are essential in determining whether IVIG is useful for a particular person or not.

I hope that this clears up some confusion. - j