I once developed really bad hives (urticaria) that was diagnosed by an allergy specialist as auto-immune urticaria. No specific cause (other than my immune system dysfunctioning) was established. I can't remember what UC med I was on at the time I'm afraid - I'd have to look through my medical letters.
Have you had your liver function tested recently? That can sometimes be a cause of itchy skin, although the fact it's happening for you with water and you're getting a rash that comes and goes by the sound of it suggests yours is unlikely to be related to liver function.
Post Edited (UCyousee) : 7/4/2021 11:27:34 AM (GMT-6)