Allergy Blood Test vs. Skin Test

April 21, 2023

Leon Robinson

What are allergies?

Allergies occur when our immune defense system overreacts to a foreign substance such as pollen, animal dander, or a certain type of food.  These allergens are mistakenly identified as harmful by the immune system causing the production of antibodies.   These antibodies cause the release of histamine.  It is histamine that causes the symptoms we typically associate with an allergic reaction.

Identifying the triggers that cause allergy symptoms is the first step toward an allergy diagnosis. Allergy symptoms most often affect the skin, eyes, nose, stomach, sinuses, and lungs. Common signs of an allergic reaction can include:

  • Abdominal pain
  • Coughing
  • Diarrhea
  • Dry skin
  • Eczema
  • Headaches
  • Hives (urticaria) and swelling (angioedema)
  • Itchy, red, or watery eyes
  • Nausea and vomiting
  • Shortness of breath (dyspnea)
  • Skin rash
  • Sneezing
  • Sore throat (pharyngitis)
  • Stuffy, itchy, or runny nose
  • Swollen lips, tongue, eyes, or face
  • Wheezing, tightness in your chest, or allergic asthma

How do you test for allergies? 

Dealing with allergies starts by identifying which triggers are causing your allergic reaction.  Once you know the cause of your allergies, you and your doctor can develop an allergy treatment plan that includes allergen avoidance, medications, or medication (immunotherapy). 

There are two common clinical ways to test for allergy triggers, skin prick testing, and blood tests. Both testing methods work by detecting antibodies, called Immunoglobulin E (IgE) to specific allergens.

Allergy skin tests are normally performed on the inner forearm but are occasionally done on the upper back. A small drop of each allergen is placed on the skin and then pricked with a special lancet through the drop. A small red bump will usually form within 15-20 minutes at the site of allergens that trigger a reaction.

Blood allergy testing is done with a simple blood draw from your arm.  Once your sample is collected, it will be sent to a lab for testing.  Results are usually available within a few business days.

Blood Vs Skin Allergy Testing

There are advantages and disadvantages to both methods of allergy testing. 

Skin testing requires very little wait time to see results.  In some cases, skin testing can be more sensitive to detecting certain allergens than blood testing.  Skin testing requires exposure to various allergens, albeit in very small amounts.  While the risks are minimal, some people do have more severe reactions and have even gone into anaphylactic shock while undergoing skin allergy testing.  Certain skin conditions like rash or hives as well as medications such as histamines can prohibit people from taking a skin scratch test.  Skin testing is usually performed at a doctor’s office which can add additional time and expense to the process.

One of the primary advantages of blood allergy testing is that it can be done at almost any laboratory patient service center with little to no advance notice.  While blood testing usually takes a few days to get results, there’s no need to schedule a doctor’s appointment and you can interpret your own test results.  Blood testing does not require any exposure to actual allergens so there is no risk of a negative reaction.  Blood allergy test results provide a numerical value that makes it easier to quantify the severity of your allergic reaction than a skin test.  Like any test that requires a blood draw, people with an aversion to needles may be uncomfortable with a blood allergy test.   

Which type of allergy testing is best?

There is no one size fits all strategy for allergy testing.  There are pros and cons to both skin and blood testing.  You can determine which factors are most important to you.  Consider the speed, convenience, cost, and physical requirements of each type and pick the one that suits you best.  It can also help to consult your doctor to see which test they think will be most effective in your circumstances. 

Where can I get a blood allergy test?

If you are looking for allergy testing that you can fit into your schedule and be done close to you, look no further.  Request A Test offers a wide selection of affordable blood allergy tests that are easy for anyone to order. There is no need to schedule a doctor’s appointment and no insurance is necessary.  Just pick from over 4,000 lab locations, order your test, and go get tested. We can order individual antibody (Ige) tests for specific allergens or bundle multiple allergen tests together for extra savings and convenience. We offer Food Allergy Panels to help determine if a person may be allergic to common food items.  We have panels that include testing for different types of grains, dairy, meat, seafood, shellfish, vegetables, pet dander, and more.  We also offer 19 individual Respiratory Allergy Panels to help measure a person's reactions to allergens in a particular geographic area.

If you’re unsure which type of allergy test is right for you or have more questions about the process of taking an allergy blood test, our team is ready to help.  Call our office during business hours at 888-732-2348 to to discuss your options or get assistance placing an order.  You can also order online any time and go to the lab as early as the same day.

DISCLAIMER: The medical information in this post is for informative purposes only.

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DISCLAIMER: The medical information in this post is for informative purposes only

Click to read our full disclaimer.

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