Hi Dear,
Welcome to HCM.
Understanding your concern. As per your query you have huge red welts on stomach, back and arms. Well there can be many reasons for symptoms you mention in query like allergic reactions, chemicals in certain foods, insect stings, sunlight exposure , side effects of medications , some common foods nuts, chocolate, fish, tomatoes, eggs, fresh berries, and milk. I would suggest you to avoid trigger factors given above , take over the counter anti
histamine like zyrtec and apply cold compresses on welts to reduce inflammation and
redness . If condition doesn't get better then
consult dermatologist for proper examination . Doctor may prescribe immunosuppressants or
steroids along with corticosteroid ointment . Doctor may also give
adrenaline short in severe case . Also keep yourself hydrated.
Hope your concern has been resolved.
Get Well Soon.
Best Wishes,
Dr. Harry Maheshwari