I've been taking PTU since November 2005 when I was diagnosed with Graves Disease when being 3 months pregnant. I had no obvious symptoms, I couldn't even tell my heart was racing. I only noticed that I felt very out of breath when I did exercise - but just put that down to being unfit!! My hormone levels were six times higher than they should be and I was put on a low dosage of 150g of PTU a day because of the pregnancy. I probably had undiagnosed Grave's Disease for many years, possibly even 7! My hormone levels instantly came down to an acceptable level and luckily I had no side effects with myself or my daughter. After the birth my endo increased my dosage to 200g a day, but told me I would have to think about having Iodine treatment or surgery in future. I've been recommended to have surgery because of the problems with radioactive iodine and children. If I come off the dosage, my levels instantly go back up. Does anyone know if I can just stay on this drug forever - are there any long-term side effects? I don't suffer from any bad side effects using it and would much prefer to continue taking it forever than go through surgery.