I have been living with POTS for 9 months but was just diagnosed about 3 weeks ago. To take a class at the University in my town, you have to have proof of immunizations for measles, mumps, and rubella. I want to enroll and take a course this summer, but I have to have proof that I either had the disease or proof of immunization. I took the blood test and it showed that I have no immunity to rubella or mumps and very little for the measles (even though I was immunized multiple times over the years). And since I am 44 years old, my mother no longer has my shot records!! That means I have to get the MMR shot if I want to take a class. Since I am new to this POTS stuff, I was just wondering if anybody knew how a shot like that might affect those of us with compromised systems. I'd hate to make things even worse! Thanks for your help and insight!!!