How to prepare for patch testing

Day 1: Application

During your first appointment, I'll apply small patches containing common allergens to your back. These patches contain standardized amounts of substances like fragrances, preservatives, metals (like nickel), and other chemicals commonly found in everyday products. The patches are secured with hypoallergenic tape and must stay dry and in place.

Bring your products with you to this visit so we can review ingredient lists. We may also make custom patches out of some of your personal care products.

Day 3: Removal

Patches are removed 48 hours after placement. Some reactions may be visible at this point, but many take longer to develop. This can be done at home or in the clinic.

Day 5-7: Final Reading (Friday or Monday)

This is the most important visit. I'll examine each test site for signs of allergic reactions, which can range from mild redness to more significant inflammation. The delayed nature of these reactions is why this final reading is crucial – many allergens don't show their true colors until this point.

What the Results Mean

A positive result doesn't automatically mean that substance is causing your current skin problems – it means you're allergic to it and should avoid it going forward.

Preparing for Your Patch Test

To ensure accurate results:

  • Stop topical steroids on your back 1 week before testing

  • Avoid oral steroids and immunosuppressants during testing if possible

  • Don't get a sunburn or tan on your back before testing

  • Inform me of all medications you're taking

  • Bring a list of products you use regularly (we might test some of these too!)

After Your Patch Test

Once we identify your specific allergens, the real work begins. I'll provide you with:

  • A comprehensive list of products to avoid

  • Alternative product recommendations

  • Guidance on reading ingredient labels

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