hi nikkii had hyperthyroidism as a child and now i just got diagnosed - 28 years later - with hypothyoidism. it runs in my family. i've had ibs-d since my mid-teens. as far as i know, there is no correlation between these two diseases. i might be wrong, and please correct me if i am, but i dont think ibs is classified as an "autoimmune" illness, but thyroid problems are. both ibs and thyroid problems run in my family. i just got lucky i guess and got both! (yes, that is sarcasm)i'm on levothyroxine now. as a child i took propylthyrocil, which i'm sure i'm spelling wrong. as far as we know, i'm the only family member who had hyper as a child and hypo as an adult. gee, do i get a prize??take care!