I have many allergies and reported this to my doctor, including previous reactions to iodine. There is a new product (relatively new-still derived from iodine) which does not cause as many problems. Be sure you ask about that. I used to get very warm during those tests and people stood by to treat a sever reaction. Withe the newer kind this did not happen. I had no reaction. Be sure you ask , and ask again if you are not happy with the answer. Mary Ann is correct. Nita Andres, RN, MPH ( I rarely put that down-but there it is)