What is a ROAT?

A ROAT is a way to check if a product is causing an allergic reaction on your skin. It involves applying the product to a small patch of healthy skin and watching for a reaction over a few days or weeks. It is often used if you want to see if a product is causing your skin problems or you are waiting for a patch test.

Which products can you test?

ROAT is only safe for products normally applied to small areas of healthy skin.

• Leave-on products: creams, moisturisers, sunscreens, perfumes
• Wash-off products: shampoos, body washes (applied and rinsed like normal use)

What products are NOT suitable for a ROAT?

Do not use products that could be unsafe or irritating, such as:

• Household cleaning products (bleach, detergents, oven cleaners)
• Strong acids or chemical peels (glycolic acid, salicylic acid, retinoids)
• Products that can cause systemic reactions (oral medications, injectables)

 How to do a ROAT

1. Choose a 2×2 cm area on your forearm
2. Make sure the skin is healthy and free from eczema or rashes. Do not use steroid creams on the test area while doing ROAT – they can hide reactions.
3. Mark the area with a skin-safe marker or tape to outline the patch. This helps you apply the product to the same spot each time
4. Apply a thin layer of the product twice a day (morning and evening)
5. Continue for 2 weeks (14 days)
6. Keep a daily diary of the patch area and note any redness, itchiness, swelling or blistering

What do the results mean?

• No reaction → The product is unlikely to be causing your skin problem
• Reaction occurs:

1. Stop using the product immediately
2. Avoid applying it anywhere else
3. Take photos of your reaction, product/s, and ingredients; seek advice if required/advised