Contact Dermatitis

What is contact dermatitis?
Contact dermatitis is a physiological reaction that occurs after skin comes in contact with certain substances.

About 80 percent of these reactions are irritant reactions and 20 percent are allergic reactions. In allergic reactions, the reaction may not be immediate, but may start after several days.

Adults are affected by allergic contact dermatitis more than young children or the elderly.

What does contact dermatitis look like?
The skin becomes red, itchy and inflamed, often with blisters. The most severe reaction is at the contact site. Scratching the area will spread the rash, in most cases.

What causes allergic contact dermatitis?
Plants, as well as metals, cosmetics, and medications may cause a reaction.


Treatment for Contact Dermatitis

According to the American Academy of Allergy, Asthma and Immunology:

Avoiding substances that may cause allergic contact dermatitis is best. For mild to moderate reactions, follow these precautions:

1. Thoroughly wash skin with soap and water as soon after exposure as possible.

2. Wash clothing and all objects that touched plant resins to prevent re-exposure.

3. Use wet, cold compresses to soothe and relieve inflammation if blisters are broken.

4. Calamine lotion may relieve itching. It also acts as a drying agent.

5. For severe reactions, contact your physician.


  • Poison ivy
    Poison ivy, which is part of a plant family that includes poison oak and sumac, is the most common cause.
  • Metals
    Nearly 3,000 chemical agents are capable of causing allergic contact dermatitis. Nickel, chrome, and mercury are the most common metals that cause contact dermatitis:
  • Nickel is found in costume jewelry, belt buckles and wristwatches, as well as zippers, snaps and hooks on clothing.

  • Contact with objects that are chrome-plated, which contain nickel, will probably cause skin reactions in people sensitive to nickel.

  • Mercury, which is found in contact lens solutions, cause problems for some sensitive individuals.
  • Cosmetics
    Many types of cosmetics can cause allergic contact dermatitis.

    Permanent hair dyes that contain paraphenylenediamine are the most frequent causes.

    Other products that may cause problems include dyes used in clothing, perfume, eye shadow, nail polish, lipstick, and some sunscreens.

  • Medications
    Neomycin, which is found in antibiotic creams, is the most common cause of medication contact dermatitis. Penicillin, sulfa medications, and local anesthetics, such as novocaine or paraben, are other possible causes.