Can You Take Claritin Before An Allergy Test?

In our latest question and answer, the pharmacist discusses whether or not the antihistamine Claritin (loratadine) can be taken before an allergy test.

Apr 23, 2018

Jojo asked

My son is to have allergy testing done Thursday morning. My husband gave him a Claritin on Sunday. He has not been taking his medication. Do we need to reschedule this appointment or should it be okay?

Answer

In most cases, antihistamines like Claritin (loratadine) should be avoided before an allergy test as they can blunt your allergic response, and therefore, potentially affect your test results.

Allergy Testing

Allergy testing is an important tool that medical professionals use to identify possible allergy causing agents you may be sensitive to and develop a proper treatment plan. Testing can help diagnose allergies that include eczema, different types of food, medication, and latex.

Certain medications can affect the results of an allergy test. You should receive a list when you schedule the allergy test that tells you what medications to avoid and how long before the test you should stop taking them.

You should check with your office specifically to verify what medications should be avoided for the specific test they are using and for how long. In many cases, different doctors have a list and requirements that differ.

As an example, below is a list of medications your office may ask you to stop taking, anywhere from 3 to 10 days prior to your allergy test:

  • Claritin, Alavert (loratadine)
  • Zyrtec (cetirizine)
  • Benadryl (diphenhydramine)
  • Allegra (fexofenadine)
  • Zantac (ranitidine)
  • Tagamet (cimetidine)
  • Xyzal (levocetirizine)
  • Vistaril (hydroxyzine)
  • Desipramine
  • Nortriptyline
  • Cyproheptadine

The above is just an example of commonly included medications that should be avoided prior to an allergy test. The list your doctor gives you may be more comprehensive. Please refer to your specific office for an official list for your test.

Ready for a more personal experience with your meds?