Knowing how to prepare and what to expect during a patch allergy test is difficult enough, but a positive patch test result can be its own scary experience. A positive result typically means that your skin will have an adverse reaction to an allergen, which can include anything from faint redness to severe itchiness. It can be difficult to anticipate the end of testing while your skin is reacting. Along with our main resource for Allergy Patch Testing, this guide is designed to assuage some of the fear and anxiety you may have with symptoms of a strong allergic reaction.
Testing positive for an allergen can manifest as a variety of reactions. In most cases, the skin will become red and inflamed. As a rule of thumb, the bigger the wheal, the more intense the allergy. However, the test is not always accurate. False positives and false negatives occur frequently, and you may react differently to the same test performed on different occasions. That said, only your doctor can make that determination.
It is important to remember that allergen patch tests are designed to detect delayed allergic reactions, which may take several days to develop. As a result, you may not experience a positive test outcome until the test plates are removed. If you are looking for a test to detect an immediate allergic reaction, this may not be the test for you.
A positive test can result in several sensations. The skin underneath the plate will become inflamed and itchy, sometimes mildly painful. However, only a very small piece of skin will experience this reaction, so the itch or pain will should not be overwhelming or very distracting. If your skin is extremely itchy or painful, contact your doctor immediately.
After the patch test is applied, you will have two separate follow-up appointments. The first will consist of the patch test removal. Here, the doctor will carefully remove the plates from your skin and wipe away any excess allergen substances. They will conduct a brief examination and note any initial observations, but you will not get a diagnosis. The doctor may also take photos of your skin for ease of comparison.
Whether your skin reacted to the initial patch testing, you will need to return to your doctor between 2 and 5 days after the plate removal. Patch testing is designed to detect delayed allergic reactions, which means a positive test could bloom even after the allergen is removed. At the follow-up appointment, your doctor will conduct a more extensive examination and compare your skin to how it appeared after the initial removal.
Most often, this second exam is where you will receive a diagnosis, typically based on visual observation alone. If you test positive for an allergy, you might also get an initial treatment plan. While a more extensive and sustainable plan may be developed later, this temporary plan will work to eliminate the allergen from your life quickly. This could include making changes to your environment, wearing protective coverings if the allergen is occupational, or making changes to your diet.
If you test positive for an allergen, one of our doctors will work with you to develop a treatment plan for allergic dermatitis. This can include medications, dietary changes, immunotherapy, and/or changes to your work or home environment. Our doctors know that plans should be tailored to your specific needs, helping you take control of your exposure and response to an allergen. If you have any questions, concerns, or want more information about how your treatment plan is designed, talk to your doctor. Receiving a positive allergy diagnosis typically means you will need to change your lifestyle in some way. If that lifestyle change is not reflected in a treatment, it will not be sustainable.