What Type Of Specialist Doctor Should I See For Recurrent Itchy Rashes On The Body?

I have experienced, over the last ten years or so, an itchy rash that would come and go and appear on different parts of my body. Usually my hands, calves, or top of my feet. It has been treated by a dermatologist with topical steroids as atopic dermatitis. Recently my face has become red, and my ankles, calves and thighs have swelled up and my whole body is covered with a red rash. I recently saw an allergist who tested for most common allergens ( environmental and food) in my area, and the results were all negative. I also switched my blood pressure medicine from lisinopril+HCTZ 20/12.5mg to losartan 50mg in order to rule that out. My entire body is very itchy as well and I have been taking hydroxyzine to ease the itch. Recently I have tapered myself off of Zoloft 50mgb ( which I had been on for 11 years for anxiety) to see if that is related. It has been about two weeks since going off of that. My skin has also been flaking very heavily at times. My allergist also had my blood tested for autoimmune disorders which came back negative as well. Any recommendations as to what type of specialist to see next? Thanks.
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