Allergies can be annoying and, in some cases, life-threatening. If you start sneezing and get watery eyes every time you rub a cat, chances are you are allergic to cats. But for some people, it’s not clear what’s causing their allergic reactions. Although you can go to a doctor who specializes in allergies, you may feel tempted to buy an at-home allergy test to learn what you’re allergic to. Should you skip the allergist and use an at-home allergy test?
What is an allergy?
Here’s a quick introduction to allergies:
An allergy occurs when your immune system reacts to a foreign substance, called an allergen. An allergen can be something you eat, inhale into your lungs, inject into your body, or touch.
An allergic reaction can cause coughing, sneezing, hives, rashes, itchy eyes, a runny nose, and a scratchy throat. Importantly, in severe cases, anaphylaxis can lead to death if you don’t receive prompt treatment.
Unfortuantely, there is no cure for allergies. However, you can manage your allergies by preventing or limiting exposure and/or using allergy treatments.
What is anaphylaxis?
Anaphylaxis is a severe, life-threatening allergic reaction. It can happen within seconds or minutes of exposure to something you’re allergic to. Common triggers include certain foods, some medications, insect venom and latex.
In anaphylaxis, the immune system releases chemicals that can cause your body to go into shock. When this occurs, your blood pressure drops suddenly and your airways narrow, blocking your breathing. Additionally, you may have a rapid, weak pulse, you may get nauseous and vomit, and you may develop a skin rash.
If you develop anaphylaxis, you need an immediate injection of epinephrine (such as with an EpiPen®). Even after an injection of epinephrine, you need to go to an emergency room. Importantly, if you do not receive immediate treatment, you could die.
How many people have allergies?
If you suffer from allergies, you are not alone! In fact, 100+ million people in the US experience various types of allergies each year. And allergies are the 6th leading cause of chronic illness in the US.
How common is anaphylaxis?
Allergy testing can help you manage your allergic reactions.
To manage your allergies, you must discover the cause of your allergic reactions. Do you need an allergist, or can you trust an at-home allergy test?
Read below to learn more about testing for environmental allergies and for food-related allergies.
Should you use an at-home allergy test for environmental allergies?
Allergies to dust, mold, grasses, cats, and other environmental allergens can make you feel pretty miserable. Therefore, it is important to figure out what you are allergic to so you can take steps to minimize your exposure.
Diagnosis of environmental allergies by a doctor.
Doctors who specialize in allergies (allergists) take a complete medical history, including detailed information regarding your symptoms. Additionally, they may perform a skin test and/or take a blood sample to identify which environmental allergens trigger your reaction(s).
- Skin test – for this test, the doctor will prick your skin in numerous spots, and insert small amounts of the proteins found in common allergens. If you are allergic to a substance, the area will likely develop a bump.
- Blood test – a blood sample is sent to a lab, where a technician will test your blood against various environmental allergens to look for Immunoglobulin E (IgE) antibodies – a protein the immune system produces to fight off irritants. This test is also called a RAST test or an ImmunoCAP test.
Importantly, both of these tests can give you false positive or false negative results.
However, experts believe a doctor’s visit, along with these tests, provide a more personalized, in-depth analysis than at-home tests.
Diagnosis by an at-home allergy test.
For at-home allergy tests, you (or a lab) send in your blood sample to the testing company. Upon receiving your sample, they conduct an IgE test to look for antibodies.
If you want to use an at-home test, you must gather a sample of your blood. Some at-home allergy tests require you to go to a lab to have your blood drawn, while others have you gather your sample at home. If you can’t imagine yourself pricking your own finger to retrieve a blood sample, then you should use a test that requires a blood draw at a lab.
How accurate are at-home environmental allergy tests?
Although these at-home tests can help you identify allergens, some experts believe the analysis you receive from an at-home test is not as thorough as the analysis performed by a doctor. Importantly, the results from at-home allergy tests can be inaccurate or misleading.
However, an at-home test can be a first good step, especially if you face a long wait to see an allergist. But keep in mind that experts think at-home tests are not as accurate or sensitive as testing done in a doctor’s office.
Pros and cons of at-home environmental allergy tests.
- Easy to use.
- A blood sample analysis is not as thorough as a full evaluation done by a doctor.
- Results can be inaccurate or misleading.
- Tests are expensive and likely not covered by insurance.
Should you use an at-home allergy test for food allergies?
How common are food allergies?
As of 2021, approximately 16 million adults and 4 million children in the US have food allergies.
- Milk is the most common allergen for children, followed by eggs and peanuts.
- Shellfish is the most common allergen for adults, followed by peanuts and tree nuts.
Food allergies vs. food intolerances.
Importantly, don’t confuse food allergies with food intolerances, which can cause abdominal pain, gas, diarrhea, constipation, and other GI issues.
If you experience food-related symptoms that are not severe or immediate, testing done at your doctor’s office and testing done at home will not likely identify which foods you cannot tolerate.
Diagnosis of food allergies by a doctor.
Unfortunately, there is no easy way for doctors to confirm or rule out food allergies.
However, doctors do their best to identify food-related allergies. Firstly, your doctor will ask about your symptoms and take a thorough family history. Additionally, your doctor will consider the following evaluations:
- Physical exam.
- Skin test – similar to the test used for environmental allergies. Note that a positive reaction in this test is not enough to confirm a food allergy.
- Blood test – to measure IgE levels after exposure to different foods.
- Elimination diet – your doctor may ask you to eliminate suspected foods for 1-2 weeks, then add food items back into your diet one at a time. Importantly, this type of testing is not foolproof and can be dangerous for people who have had severe reactions in the past.
- Oral food challenge – while at the doctor’s office, you are given small amounts of suspected foods, gradually increasing the quantity eaten.
Importantly, some of these tests can misidentify food allergens that do not cause you harm, leading to false positives.
Diagnosis of food allergies through at-home tests.
If you want to use an at-home food allergy test, you will need to send in a sample of your blood. Like at-home environmental allergy tests, some companies ask you to do a finger prick, while others require a visit to a blood lab. The company then tests your blood for antibody responses.
Are at-home food allergy tests reliable?
Experts say no.
Importantly, at-home food allergy tests cannot officially diagnose a food allergy. Instead, they can help identify foods that you might be allergic to.
The American Academy of Allergy, Asthma, & Immunology (AAAI) states that at-home food allergy tests have never been scientifically proven to be able to accomplish what testing companies claim.
Additionally, for years, doctor groups have advised against using IgG tests to evaluate for food sensitivities or intolerances. Moreover, allergy experts state the test is useless at best and could even cause harm if it leads customers to unnecessarily cut nutritious foods from their diet. And a 2008 European Academy of Allergy and Clinical Immunology task force recommended against testing for a type of IgG to evaluate for food intolerance.
Lastly, ASCIA (the Australasian Society of Clinical Immunology and Allergy) states that the following types of tests do not provide evidence based clinically useful results, can lead to adverse outcomes, and are a waste of time and money:
- Any tests that claim to ‘screen’ for food allergy, including genetic tests.
- Food allergy tests that are ordered online.
- Tests for Immunoglobulin G (IgG) response to foods.
- Unproven, non-evidence-based allergy ‘tests’.
Risks of at-home food allergy tests.
Receiving inaccurate test results from at-home food allergy tests can impact your health in the following ways:
- False positive results can lead to anxiety and cause you to make unnecessary changes to your diet, which can lead to unhealthy, unbalanced diets.
- Additionally, a false positive result can lead you to overlook the possibility that you may have a gastrointestinal condition such as irritable bowel syndrome or Chron’s disease.
Testing companies claim success.
Despite evidence to the contrary, EverlyWell says their at-home food sensitivity test can gauge whether a person’s immune system is active against 96 common foods. They claim their test analyzes a finger prick of blood to identify the presence of an immune protein called immunoglobulin G (IgG).
Their website states that an elevated IgG reactivity level can mean that food might be causing symptoms. However, they also clearly state that it does not test for food allergies, lactose intolerance, or celiac disease.
Importantly, EverlyWell’s IgG tests, and similar tests made by competitors, are not regulated by the FDA.
Using an at-home test?
If you receive results from an at-home kit that indicate a potential allergy, talk to your doctor who can help you interpret the findings and create a follow-up plan. Do not change your diet based on the results without a discussion with your doctor!
Pros and cons of at-home allergy tests for food.
- Easy to use.
- Experts believe the test results could be inaccurate and do not recommend using these tests.
- At-home food allergy tests are expensive and likely not covered by insurance.
As science progresses, at-home medical tests increasingly enter the market. Certainly, some of these tests are reasonably accurate, easy to administer, and relatively affordable. But other at-home tests are expensive and unreliable. Read these posts to learn more:
- Can You Trust At-Home Medical Tests?
- Can You Trust At-Home Cancer Tests?
- Tips for Newly Diagnosed Diabetes Patients. (This post includes information on home blood sugar testing options.)