Contact Dermatitis

Picture of contact dermatitis from poison ivy

Illustration copyright 2000 by Nucleus Communications, Inc. All rights reserved. http://www.nucleusinc.com

Many rashes are caused by contact with a substance that causes an allergic reaction (contact dermatitis). The rash usually starts within 48 hours after a person is exposed to the irritating substance, but it may not show up for several days. A minor case of contact dermatitis may cause mild redness of the skin or a rash of small red bumps. A more severe reaction may cause swelling, redness, and larger blisters.

Common causes of contact dermatitis include:

Contact dermatitis doesn't usually occur the first time you are exposed to the irritating substance (allergen). After you have had a reaction to the substance, a rash can occur in response to even very small amounts of the substance.

Credits

ByHealthwise Staff
Primary Medical ReviewerWilliam H. Blahd, Jr., MD, FACEP - Emergency Medicine
Specialist Medical ReviewerH. Michael O'Connor, MD - Emergency Medicine
Last RevisedMay 11, 2012
By: Healthwise StaffLast Revised: May 11, 2012
Medical Review: William H. Blahd, Jr., MD, FACEP - Emergency Medicine
H. Michael O'Connor, MD - Emergency Medicine

© 1995-, Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.

This information does not replace the advice of a doctor. Healthwise disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.