Contact Allergy Testing
Patch testing is a procedure to identify if a particular substance or chemical may be causing your rash. Patch testing is used to identify substances which may be causing an allergic contact dermatitis.
Allergic contact dermatitis often presents as a type of dry and scaly rash. If you notice a particular flare up using certain products such as cosmetics or fragrance, your contact allergy may be the cause of your dermatitis.
Contact allergy may also be the cause of dermatitis around the eyes, or dermatitis which flares up very suddenly. Some patients may have long standing eczema since childhood which is aggravated later in life by a contact allergy.
The patch testing process involves using small amounts of chemicals that we are commonly exposed to and placing these onto a series of “patches” on the back. At least 60 patches are usually tested at once. The patches are applied on a Monday, and the test is read after it is removed on Wednesday and Friday the same week.
After removing the patches, the dermatologist reads your test and identifies any red areas that have reacted. If you have positive reactions, you will then be given written information on how to avoid these substances.
Some of the more common reactions that we see in the clinic include;
- Preservatives used in cosmetics and shampoo
- Nickel allergy (which may cause reactions to jewellery)
- Sunscreen allergies
- Rubber (used in gloves)
- Some topical medications
If you think you would benefit from patch testing to investigate your dermatitis, you will need to see the dermatologist first to discuss what you may need to be tested for. Certain professions come in to contact with particular chemicals which may need to be ordered in advance e.g. dentists, hairdressers, bakers and carpenters. We will also discuss whether you need to bring any of your products from home to be tested, such as your facial moisturiser or cleanser.
Please also view our Patch Testing & Skin Allergies page. After your initial visit a suitable time for patch testing will be organised and the full costs quoted prior to starting the testing process.
A referral from your GP will usually allow you to claim approximately half of the costs back from medicare.