Patch Testing

After receiving a referral from your GP, you will need to book in a consultation with one of our dermatologists to establish if patch testing is suitable for you. If you and your treating physician are happy to proceed, three consecutive appointments will be made for you over the course of 5 days. For example:

Appointment 1 (Monday): Patches are applied and kept undisturbed for 48 hours.

Appointment 2 (Wednesday): Patches are removed, reactions read and test sites marked with suitable maker.

Appointment 3 (Friday): Second reading done and results and management discussed with the dermatologist.

During your first visit, tiny quantities of various substances, usually between 25-150, are applied to the skin on your back, and kept in place with hypoallergenic adhesive tape. The aim is to test whether any of these substances cause irritation on your skin. The patches should stay in place undisturbed for 48 hours, so we will advise you to continue about your activities over the next two days taking special care of the test patches on your back.

Returning for your second appointment two days later, we remove the tape while marking each test site with a special skin-safe marker. These marks must still be visible at your third appointment, usually another two days later. We will then assess any responses to each substance, uncovering topical skin irritants so that you can better understand any triggers that lead to your skin irritation.

The process described above may vary based on the location at which you see the dermatologist.  Please check with your treating dermatologist for specific details.

Patch testing is not the same as prick testing. Patch testing is used to detect allergic contact dermatitis (type IV hypersensitivity reaction). This includes allergy to hair dye, shoes, active ingredients, preservatives and fragrances in sunscreens, cosmetics and medicaments. The allergic reactions usually appear 2 to 4 days after applying the allergen on the skin but it can take up to a week to react. Prick testing on the other hand is used to test type I allergy causing hay fever, asthma and contact urticaria (hives). Prick testing involves needle pricking and is read 20 minutes after skin pricking.

Patches will be placed on your body (usually back) for 3 days.

At your initial appointment, your dermatologist will ask you questions relating to your work and lifestyle. This will give them a good understanding of what allergens you may regularly come into contact with and which patch series is most relevant to you.

• The area of skin being tested must be kept dry until the final reading. Please consider this when scheduling your appointment.  

• Avoid direct sunlight exposure to the back several days prior and for the duration of testing as UV radiation may reduce the immune response in the skin.

• Keep the area of skin being tested dry until the final reading, please consider this when scheduling your appointment

• Avoid activities that make you hot and sweaty.

• Avoid excessive twisting movement which can lift the test patches.

• Do not apply any oil or cream on your back the morning of the testing.

• If you are taking cortisone/prednisolone or immunosuppressive medications, please check with your dermatologist as they can affect the result of patch testing.

• It is possible to become allergic to something that has been used for many years. If in doubt, bring along everything to show the dermatologist.

The final cost of your treatment will include an initial consultation with one of our dermatologists ($275 with a $76.80 medicare rebate) plus your three allergy testing visits at a combined rate of $453.25 with a medicare rebate of $179.35.

Great! We look forward to welcoming you to The Skin Lab. Pre-treatment preparation will be advised by your doctor as this may vary from patient to patient.

Steroid creams or medications, or antihistamines, should not be taken within 48 hours of your patch testing. Please call us for advice if you are unsure. Shower the morning of your test as you cannot get your back wet from the time your patches are applied until your third appointment. Wear a dark top, as the pens we use to mark your test sites are black or purple and may stain lighter clothing.

Do not apply any moisturisers or creams the day of your appointment. All physical activity or jobs that require sweating should be avoided as sweat can dilute the patch test sites or make the patches fall off completely. We offer certificates for work if needed.