How are skin allergies diagnosed?

Most skin allergies can be diagnosed by an experienced dermatologist who takes a thorough history and carefully examines the skin. When allergy testing is needed, there are several kinds of tests that might be helpful.  Keep in mind that not every patient requires all of these tests.

If your doctor makes a diagnosis of eczema or atopic dermatitis, the most useful tests are blood tests for antibodies against specific foods and airborne particles and skin prick tests that identify the offending substances.  

If your condition is diagnosed as allergic contact dermatitis, the best way to identify what you're allergic to is to tell your doctor all the products you've been in contact with, such as a new cosmetic product, costume jewelry, or plants you've been handling. Once you and your doctor narrow this down, skin patch testing can be done to confirm the exact substance you need to avoid.

Skin allergies and their triggers are most commonly diagnosed through skin tests, including scratch tests, prick tests, and most commonly patch tests. Skin testing usually involves a doctor applying samples of allergens to a small area of skin, usually on the forearm, and then sometimes scratching or pricking the skin to let the allergen seep in. After some time, usually anywhere from 15 minutes to 96 hours, the doctor examines the skin to determine whether there was a reaction to the substance. If a person has certain skin conditions or is taking medications that would interfere with a skin test, a blood test that analyzes levels of antibodies may be done instead.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.