Not an allergy??

Hi - New here.

I was told that UC (hives) are NOT an allergy. What are they then? And why am on FOUR OTC allergy meds??

I have had hives that look like bug bites and last about 4 days before fading since July. I get them singularly or in clusters of 2-5. I get them on my extremities, midsection and back.

I have now had three biopsies. Inconclusive so far waiting for more results.

I have been told by THREE specialists (allergist, dermatologist and Rheumatologist) that it is a result of my autoimmune diseases (RA and Sjogrens).

ALSO...if it;s not an allergy how come biopsy came back allergy of unknown cause??