Before recommending a skin test, your doctor will ask you detailed questions about your medical history, your signs and symptoms, and your usual way of treating them. Your answers can help your doctor determine if allergies run in your family and if an allergic reaction is most likely causing your symptoms. Your doctor may also perform a physical examination to search for additional clues about the cause of your signs and symptoms.
Medications can interfere with results
Before scheduling a skin test, bring your doctor a list of all of your prescription and over-the-counter medications. Some medications can suppress allergic reactions, preventing the skin testing from giving accurate results. Other medications may increase your risk of developing a severe allergic reaction during a test.
Because medications clear out of your system at different rates, your doctor may ask that you stop taking certain medications for up to 10 days. Medications that can interfere with skin tests include:
April 02, 2014
- Prescription antihistamines, such as levocetirizine (Xyzal) and desloratadine (Clarinex).
- Over-the-counter antihistamines, such as loratadine (Claritin, Alavert), diphenhydramine (Benadryl, others), chlorpheniramine (Chlor-Trimeton), cetirizine (Zyrtec, others) and fexofenadine (Allegra).
- Tricyclic antidepressants, such as nortriptyline (Pamelor) and desipramine (Norpramin).
- Certain heartburn medications, such as cimetidine (Tagamet) and ranitidine (Zantac).
- The asthma medication omalizumab (Xolair). This medication can disrupt test results for six months or longer even after you quit using it (most medications affect results for days to weeks).
- Nolte HN, et al. Overview of skin testing for allergic disease. http://www.uptodate.com/home. Accessed Nov. 26, 2013.
- AskMayoExpert. How are allergy skin tests performed? Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2013.
- AskMayoExpert. What are the primary indications for allergy testing? Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2013.
- Tips to remember: What is allergy testing? American Academy of Allergy, Asthma and Immunology. http://www.aaaai.org/patients/publicedmat/tips/whatisallergytesting.stm. Accessed Nov. 26, 2013.
- Allergy testing. American College of Allergy, Asthma & Immunology. http://www.acaai.org/public/background/testing.htm. Accessed Nov. 16, 2013.
- AskMayoExpert. What types of medications can interfere with allergy skin testing, and for how long should they be avoided before testing? Rochester, Minn.: Mayo Foundation for Medical Education and Research; 2013.
- Holgate ST, et al. Allergy. 4 ed. Edinburgh, U.K.: Elsevier. 2012. http://www.clinicalkey.com. Accessed Dec. 13, 2013.
- Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 5th ed. Edinburgh, U.K.; New York, N.Y.: Mosby Elsevier; 2010. http://www.clinicalkey.com. Accessed Dec. 13, 2013.