I've been on PTU for nearly 3 weeks now as i had a bad reaction to carbimazole so had to stop that. I'm actually starting to feel a bit better from my hyperthyroid symptoms but I have very itchy legs and am now getting a rash on both legs below the knee. Am taking an LA antihistamine (Boots hayfever) which is helping but I was woken up in the night with the itching. The packet insert says to tell the doctor if you get a rash but of course it's now a long holiday weekend and in any case I have an appointment with my GP a week on Monday. Is there anyone else who has had the same thing and is it important? There don't seem to be many people on the discussions taking PTU as most seem to manage on carbimazole so I feel a bit alone!