<<Disclaimer: Verify this information before applying it to your situation.>> The safety of a flu shot may depend on your own immune system, not anything inherent in the shot itself. My son has always had strong reactions to anything effecting his immune system - he's asthmatic, viruses hit him hard, routine childhood shots produced stronger than expected reactions, etc. When he was almost 5 years old, and 8 months gluten-free after the celiac diagnosis, he had a flu shot, because he was in several high risk factor categories. Seven days later he developed serum sickness, a hypersensitivity reaction to the shot. Basically in serum sickness "the immune system misidentifies a protein in antiserum as a potentially harmful substance" - which sounds very similar to the definition of celiac disease to me. (from http://www.nlm.nih.gov/medlineplus/ency/article/000820.htm ) He had high fevers for 6 weeks, total body rashes, febrile seizures, swollen lymph nodes and was utterly miserable. Supposedly the chances of serum sickness are something like 1 in 10,000,000 - unless you have an immune system problem. In that case your risk is believed to be higher, but as nobody tracks these things, nobody can really say how high your risk level is. Maureen *Support summarization of posts, reply to the SENDER not the CELIAC List* Archives are at: Http://Listserv.icors.org/SCRIPTS/WA-ICORS.EXE?LIST=CELIAC