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Hives

Hives

Overview

Hives are raised red welts of various size on the surface of the skin, often itchy, which come and go. Also called urticaria, hives is usually part of an allergic reaction to drugs or food. The term "dermatitis" describes an inflammatory response of the skin, caused by contact with allergens or irritants, exposure to sunlight, or by poor circulation, even stress. AVOID SCRATCHING. Scratching the rash may spread the inflammation, lead to infection and even leave scars.

Review Date 5/31/2023

Updated by: Ramin Fathi, MD, FAAD, Director, Phoenix Surgical Dermatology Group, Phoenix, AZ. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.