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Hives (urticaria) - close-up

URL of this page: //medlineplus.gov/ency/imagepages/2482.htm

Hives (urticaria) - close-up

Overview

Hives (urticaria) are raised, red, itchy welts. The majority of urticaria develop as a result of allergic reactions. Occasionally, they may be associated with autoimmune diseases, infections (parasitosis), drugs, malignancy, or other causes.

Review Date 3/31/2024

Updated by: Deborah Pedersen, MD, MS, Allergy & Asthma Care, PC, Taunton, MA. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.