What is allergic contact dermatitis?
Allergic contact dermatitis, a common disorder in Australia, is a red, scaly and itchy rash (similar to atopic dermatitis) that forms when your skin comes into contact with a substance that causes you to have an allergic reaction (i.e., an allergen). It typically occurs around the eyes and across the face and hands and often flares up. Common allergens include:
- Topical medications
- Nickel (such as in jewellery)
- Rubber (such as rubber gloves)
- Preservatives used in cosmetics and shampoo
What is patch testing?
Patch testing is a medical procedure (the most reliable way) used to identify the substance that is causing your allergic contact dermatitis. This procedure puts small amounts of common substances on a series of patches on the back. At least 60 patches are usually tested at once.
After removing the patches, the dermatologist checks for any reactions, such as red areas. If you test positive for any reaction, the dermatologist will provide you written information on how to avoid the allergen(s). Simply completely avoiding the allergen(s) may cause the dermatitis to subside.