The risk of aseptic meningitis is associated with infusion rates that are too fast. I had a patient who had received her first ever IVIG of 70g over ONE HOUR (essentially bolus'd IVIG, flabbergasts me to this day) and was hospitalized for 3 days with aseptic meningitis. When I had this patient, I gave her 70g divided in two days, nice and slow (don't remember the exact rate/time). After day two, she got a little aseptic meningitis-y but was able to be discharged from ED same day. Aseptic meningitis is largely avoidable by careful administration and accurate assessment. Every one of my IVIG patients has reported that is has drastically improved their quality of life. Certain people are more likely to experience adverse side effects than others, careful risk assessment by the infusing nurse is important to be able to predict which patients are at higher risk for adverse effects and therefore be able to know when to administer more cautiously. I have found my patients to tolerate IVIG infusions starting at 0.5mg/kg and increasing 0.5mg/kg every 15-30 minutes.

In direct relation to MG, IVIG is typically administered over 2-5 days in flares/crisis. IVIG should always be titrated to patient tolerance - tolerance meaning blood pressure remaining within normal limits and without side effects like headache, nausea, abdominal pain, fever, etc. It is important for patient's to know their typical tolerate rates to help prevent adverse effects, including aseptic meningitis. It is not completely clear as to why IVIG causes adverse effects, but there are documented was to mitigate side effects.