Hives are small, itchy, red swellings on the skin. The swelling occurs singularly or in clusters. Hives tend to fade after a few hours, but new ones can appear. Most cases go away within a few days. But, some last a few weeks or longer.
Hives are often caused when the body releases a chemical called histamine. Histamine is released during an allergic reaction. Many people, though, get hives without being exposed to something they are allergic to.
While the cause is unknown in some cases, these factors may cause hives:
A risk factor is something that increases your chance of getting hives. Tell your doctor if you have any of these:
Symptoms of hives can vary from mild to severe:
The doctor will ask about your symptoms and medical history, and perform a physical exam. You may need to see a doctor who specializes in skin disorders (dermatologist) or allergies (allergist). The following tests will be done:
The best way to treat hives is to find and then avoid the cause.
If the cause can't be found, there are medications to treat hives:
RESOURCES:
American Academy of Allergy, Asthma, and Immunology
http://www.aaaai.org/
American Academy of Dermatology
http://www.aad.org/
CANADIAN RESOURCES:
Canadian Dermatology Association
http://www.dermatology.ca/english/
Dermatologists.ca
http://www.dermatologists.ca/index.html/
References:
Dibbern DA Jr. Urticaria: selected highlights and recent advances. Med Clin North Am. 2006;90:187-209. Review.
Gambichler T, Breuckmann F, Boms S, Altmeyer P, Kreuter A. Narrowband UVB phototherapy in skin conditions beyond psoriasis. J Am Acad Dermatol. 2005;52:660-670. Review.
Guldbakke KK, Khachemoune A. Etiology, classification, and treatment of urticaria. Cutis. 2007;79:41-49. Review.
National Institute of Arthritis and Musculoskeletal and Skin Diseases website. Available at: http://www.niams.nih.gov/ .
Skin biopsy. EBSCO Health Library website. Available at: http://www.ebscohost.com/thisTopic.php?marketID=15topicID=81 . Updated October 2007. Accessed June 17, 2008.
Tips to remember: allergic skin conditions. American Academy of Allergy, Asthma, and Immunology website. Available at: http://www.aaaai.org/patients/publicedmat/tips/allergicskinconditions.stm . Accessed July 7, 2008.
Urticaria/angioedema. EBSCO DynaMed website. Available at: http://www.ebscohost.com/dynamed/what.php . Updated June 2008. Accessed July 7, 2008.
Urticaria – hives. American Academy of Dermatology website. Available at: http://www.aad.org/public/publications/pamphlets/skin_urticaria.html . Updated June 2008. Accessed July 7, 2008.
Last reviewed November 2008 by Ross Zeltser, MD, FAAD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
Copyright © 2007 EBSCO Publishing All rights reserved.