Keep in mind, the lower the pump pressures, the longer the Infusion takes. What this can also mean, is that the person administering might want it to go faster for their benifit, not necessarily yours. This is why I recommend that the doctor tells them what pump pressures, so that there's no question. Higher pump pressures alone can cause headaches. I had nasseau and headaches for about four days, but in part because of my doctor not writing a prescription that he was supposed to have written for me. But, IVIG headaches are not entirely unusual, or are 'flu like' symptoms. However, feeling almost normal for a few days is certainly worth it! After my first five days, it took about 10 days before I noted any improvement; and that improvement lasted for about three days. The next month, I had IVIG for two consecutive days, and I had improved symptoms for about six days. Now, my new Neurologist is advising me that I'm at high risk with IVIG, because I've previously had a heart attack, and there have been studies of people having heart attacks within two weeks of having IVIG treatments.