Hey there
Im not sure what to do about it, but Ive been like that all my life too. Ive always had itchy skin and I dont have any allergies. It starts when Im nervous and anxious.
And it can go on forever. I have noticed that when Im scratching Im not breathing well, and sometimes when I relax and breathe slowly it stops. I dont think being warm helps either.

Sorry I cant help you but I understand how you feel. I wouldnt take any medication for my itching, because Im already on enough meds as it is. I just think that relaxing and solving the problems that cause me anxiety and nervousness, will work better for me.

Hope you find what youre looking for.