Just found this on another thread about itchy rash.
“this itchy rash is one of the most common side effects of decapeptyl. No idea why your onco didn’t just tell you that!
There isn’t much that can be done - you could ask about a change to Zoladex or Prostap but itchy rash is listed as a common side effect for both of those as well. Stronger prescription anti-histamines might be the best thing to try next.”