Your Guide to The Allergy Test

Your physician may request an allergy test if you show signs and symptoms of allergies, especially if they are not being treated by over-the-counter medications and after taking the precautions recommended by your doctor. These symptoms include:

• Sneezing
• Itchy, watery eyes
• Rashes in response to certain substances
• Shortness of breath
• Cough
• Wheeze
• Diarrhea
• Nausea and vomiting

A blood sample is taken from the patient through a vein in this test. It is then sent to a laboratory for testing to find the level of antibody IgE in the blood. This may take up to a few days. On the other hand, a skin test is done in the physician's office, which gives instant results within half an hour in case of immediate allergic reactions or may take up to a few hours to days in case of some other allergens that exhibit the delayed type of allergic response.

Your physician will recommend you stop using certain drugs 5-7 days before you take the allergy test. These include: 

• Antihistamines like hydroxyzine, cetirizine, fexofenadine (Allegra), 
• Tricyclic antidepressants
• Cimetidine - commonly used for heartburn
• Asthma medication like omalizumab

The allergy test result could be negative or positive. A negative test result indicates that you do not have an allergy to the particular substance tested for. Specific IgE antibodies against particular substances help you identify this and get the results. A positive test result may or may not indicate that you have an allergy to that substance. It is essential to contact your physician to find out more based on your examination and history.

No, you do not feel sick after allergy testing. Like any other blood test with a needle, this too has certain risks such as bleeding, infection, bruising, and feeling lightheaded. The sensation of pain may be felt when the needle pricks the arm or the hand. Afterward, the site may be sore. One of the common side effects of the skin test is redness around the site of allergen administration, typically called a wheal. You may also experience itching a few hours later.

No, the skin prick test barely penetrates the skin surface and it is entirely painless. It is a non-invasive test. Nothing is felt except for mild to moderate discomfort of the needle (lancet) pricking your skin.

Yes, it is good to eat something before getting the allergy test done. However, avoid any food item that may have caused a reaction to you in the past.

Well, you are just a click away if your doctor has prescribed the allergy test. Book an appointment or get a free second opinion at Yashoda Hospitals today!