With time, the lesions tend to scale and flake. If bacterial or viral infection is introduced by scratching, the affected lesions will ooze. Hives, which are different from atopic dermatitis as they are a side effect rather than a condition, are red, very itchy, swollen areas of the skin. Hives appear suddenly and may leave quickly in 1-2 hours, or can last as long as 24 hours. They often appear in clusters, with new clusters appearing as other areas clear.
Physicians refer to hives as urticaria.
Please see the Tips to Remember section concerning allergic skin conditions for more information about symptoms, diagnosis, treatments, prognosis, and causes. The Academy is not able to respond with individual answers to questions about personal health needs, diagnosis or treatment. These can safely be answered only by your doctor or other health professional who has had the opportunity to meet and evaluate your medical condition.