Do you have a skin allergy?
Most of us are familiar with the skin allergy to poison ivy. We brush past the plant with a bare leg or arm and a red, swollen, itchy rash appears several days later. We know poison ivy is the most likely cause of the rash if we were out in the woods a few days before.
If you’re experiencing redness, itching, warmth, swelling, cracking, pain or scaling and crusting anywhere on your skin, most commonly called contact dermatitis, you should see a doctor.
When to see a specialist
There are two parts to addressing contact dermatitis, according to the American College of Allergy, Asthma and Immunology. First, you want to treat the irritated skin. Next, you want to determine what caused the reaction so you can avoid that allergen or irritant in the future.
“While a dermatologist can help treat any skin reaction if the reaction repeats itself or your doctor thinks the rash is caused by something in your environment, visit an allergist who can help you determine the cause of the reaction,” says Jason Casselman, D.O., a Reid Health allergist and immunologist.
Both an allergist and the dermatologist can prescribe topical creams and oral medications to reduce and help heal skin reactions, but an allergist can offer testing that may help identify the underlying cause of the rash.
“I’ll refer a case to a dermatologist if I think there’s a primary underlying skin issue such as psoriasis, making the allergic reaction worse,” says Dr. Casselman.
When it’s an allergic skin reaction
Dr. Casselman explains that an allergic reaction is your body’s immune response to encountering a substance in your environment it thinks it has to fight.
“Red, raised, itchy lesions such as hives from a food allergy will arise quickly, within 15 minutes to one hour, and often go away, usually within 24 hours, when you remove the exposure to the allergen,” says Dr. Casselman. “A simple contact dermatitis rash is typically caused by an irritation from a substance in the environment [that] builds up and can take two or three days to develop, often staying longer until it blisters and heals over. Continued contact with the irritant will cause the rash to worsen.”
Some of the most common skin allergens and irritants include:
- Poison ivy;
- Industrial chemicals, such as nickel in less expensive jewelry or latex in rubber gloves;
- Chemicals and fragrances in personal care products such as shampoo, sunscreen, makeup and hair dye;
- Medications; and,
- Household chemicals such as cleaners and detergents.
“Even steroid creams used to help heal a rash can worsen a rash and cause allergic contact dermatitis if you’re allergic to the steroid,” says Dr. Casselman. “And eczema, which is a dry skin disease, is often triggered and worsened by food allergies, especially in children.”
How an allergist tests for allergies
Allergists rely on different types of skin testing to introduce substances to your body and watch for a reaction to see if you have a skin allergy.
“To help diagnose allergic contact dermatitis, we test skin patches with 80 common chemicals and look for a reaction after 48 hours. We do a final interpretation another 48 hours later because some reactions take a few days to develop,” says Dr. Casselman.
Once you determine a specific irritant or allergen is causing a skin reaction, you can avoid contact with that irritant to prevent the reaction in the future.
Image source: Morguefile