Allergic contact dermatitis is a common skin condition in which patients have become sensitized to a particular allergen (or chemical) in their environment and suffer from a persistent itchy rash, usually localized to the area in which the patient is exposed to the allergen. It can be extremely difficult to isolate the problem, since in many cases, patients may have been using the problem product for years without issues.
People can become “allergic” to a chemical or produce that they previously never had a problem with before. Spectrum Dermatology offers a number of allergy tests to help you determine the cause of a persistent rash or irritation.
Through history and physical examination of the patient, dermatologists can find clues to what are the allergens which may be causing the rash. However, in many cases, dermatologists need to perform tests, such as patch tests to really identify the problem clearly. Patch tests are a safe and easy way to diagnose contact allergies.
Patch tests are different from injection or scratch skin tests because they test for different allergens. In patch tests, small amounts of the possible common allergens are applied to the skin on strips of tape. A positive allergy test shows up as a small red spot at the site of the patch.
Common allergens include nickel, rubber, dyes, preservatives, medications, fragrances, poison ivy, poison oak, and related plants.
The patch test is a full one week process. Typically, the patient has to have 3 visits during a one week period. The first visit is to apply the patches. The second visit is to remove the patches. The third visit is to do the final interpretation of the results.
The reason it takes one week to perform the test is that contact dermatitis is a delayed type hypersensitivity reaction. It typically takes 5-7 days for patients to develop a rash after being exposed to a product. This is why it is difficult for patients to figure it out on their own without patch testing.
Patch tests have little or no pain. However, positive reactions cause annoying itching red bumps which look and feel like mosquito bites. The itching and bumps are gone usually in just a few short minutes or hours.
Typically it is covered by most insurances, though it may require a prior authorization.
Spectrum Dermatology provides expertise, knowledge and passion to medical, surgical and cosmetic dermatology. Our experience and reputation make Spectrum Dermatology one of the most sought-after dermatologist in the Scottsdale and Phoenix area. For more information or to set up an appointment please contact us at (480) 948-8400.