It looks like I will be going on PTU and i am wondering about the side effects. I have been on Tapazole and have recently had to go off because of a severe rash and a decrease in my liver function. The only side effects that I experienced with Tap was a constant state of indigestion. Other than like, I felt pretty good. As a matter of fact, I felt the best that I had for at least the last two years. Again, I would like to hear of your and anyone elses experience with the other drug.