What Medications Can Interfere With Your Allergy Testing?

Allergy testing has become a common, though sometimes under-appreciated, means for identifying potential allergens and other hazards. In most cases, allergy testing is an accurate means of protecting your health. However, these tests are not infallible. There are things that can interfere with the results of the test, including things you may be doing and not even know about. Here are some of the key things that can interfere with the results of your allergy testing.


For obvious reasons, any antihistamines you're taking are likely to interfere with the results of the test. Allergy tests are designed to measure the body's histamine response to certain things in order to determine what you are allergic to. If you take antihistamines in the days leading up to, or the day of, your allergy test, the antihistamines will interfere with your body's natural histamine response, potentially leading to false negatives for things you are actually allergic to.


Beta-blockers are a form of immunotherapy, and they are crucial when it comes to heart health in some cases. However, when you are undergoing allergy testing, beta-blockers can be a serious safety concern.

Any form of immunotherapy can result in a stronger response from your immune system when presented with any kind of intrusion. That means that, with beta-blockers in your system, you risk a potential anaphylactic response if there is an allergen in the test samples.

Your doctor will tell you how long to skip the beta-blockers before your allergy test. Don't skip taking them unless you are under the supervision of your doctor, because they are vital medications if you need them.

Acid Control Medications

Acid control medications for chronic heartburn, like Zantac or Pepcid, can affect the results of your allergy testing. These medications work by blocking the H2 response. That same response is a part of the body's allergy response, which will be tested as part of this process.

When you take any medications that affect the H2 response, it can lead to insufficient allergy response during the test. This means your final allergy testing results may be inaccurate, and may fail to identify things you are actually allergic to.

For more information about what can interfere with your allergy testing, talk with a doctor and an allergist, such as at Dino Peds. The more you understand, and the better you can prepare, the more accurate your test results are likely to be.