How to test for peanut allergy at home: a quick guide

Medically reviewed on August 1, 2022 by Karen Janson, M.D. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

Table of contents

• What is at-home food allergy testing?
• Preparing for an at-home test
• Everlywell: peanut allergy testing made easy

Few foods capture childhood better than lip-smacking, protein-packed peanut butter and jelly sandwiches. That is, of course, unless you have a nut allergy.

If you’re one of the 6.1 million Americans allergic to the nutritious nut, peanut butter is the less of a childhood snack and more of a lifelong caution. This is especially true if you think you might have a peanut allergy but have yet to take a food allergy test.

Fortunately, we’re here to give you the inside scoop about how to test for a food allergy at home, showing you how testing for a nut allergy can be easier than cutting the crust off a delicious almond butter sandwich.

What is at-home food allergy testing?

Like automobiles, radios, and television, food allergy testing has come a long way since its creation in the early 20th century. Dietitians administered the first food allergy test in 1921, which consisted of little more than a blood transfusion.

Since then, food allergy testing has taken many forms, including: [2]

• Intradermal tests
• Scratch tests
• Prick tests

Now, you can take food allergy tests from the comforts of your own home with at-home lab food allergy tests.

The different types of food-related reactions

Before diving into how to test for peanut allergy at home, let’s discuss the three types of food-related reactions. That way, you can be sure you’re testing for the right condition. [3]

• Food sensitivity – Food sensitivities are similar to food allergies in that they’re both driven by the presence of allergy antibodies known as immunoglobulins. However, they differ in terms of the severity of the allergic reaction. Whereas food sensitivities are typically less severe, food allergies can be life-threatening.
• Food intolerance – If food sensitivities and allergies impact the immune system, food intolerances impact the digestive system. As a result, food intolerances don’t generally produce the same negative responses as sensitivities and allergies. That said, food intolerances can lead to gas and bloating.
• Food allergy – Food allergies are the most severe allergic reaction. In addition to potentially causing swelling, hives, and digestive issues, food allergies can sometimes cause anaphylaxis.

Given the potential severity of food allergies, taking a food allergy test rather than a food sensitivity test is crucial if you think you have a peanut allergy.

How do at-home lab food allergy tests work?

Most at-home lab food allergy tests follow a similar procedure:

1. An at-home lab company sends a test kit to your home. If your kit allows you to receive digital updates and analysis, you’ll also need to register your kit with the testing company.
2. Send a blood sample to a laboratory for testing. Depending on the test, you might also send a cheek swab or saliva sample.
3. After a few days or weeks, the laboratory sends your results back to you with recommendations. The best kits use CLIA-certified labs to ensure highly-qualified dietitians and healthcare providers handle your samples.

In addition to accurate test results, some food testing kits even provide you with a personalized action plan detailing your next steps.

How do food allergy tests determine if you have a peanut allergy?

As stated above, allergy tests and food sensitivity tests both look for the presence of immunoglobulins. However, the specific immunoglobulins they isolate differ based on the test.

While food sensitivity tests look for immunoglobulins such as IgG and IgA, food allergy tests look for immunoglobulin E, also known as IgE. As it turns out, IgE plays a massive role when it comes to peanut allergies.

To understand the role IgE plays, let’s look at the reaction process from start to finish in someone who has a peanut allergy: [4]

1. A peanut-based product is consumed and peanut protein is released into the bloodstream.
2. The body releases excess IgE antibodies to bind to the peanut protein, which are now referred to as “allergens.”
3. After binding to the peanut allergens, the IgE antibodies produce histamines which trigger a negative reaction in the immune system.

Food allergy tests thus measure IgE antibody levels in the body. Too many IgE antibodies may indicate a food allergy.

How to translate food allergy test results

While some at-home test kits differ in design, most follow a standard measurement system to provide you with your results.

In short, IgE levels are recorded in units known as kU/L. At-home food allergy tests typically record kU/L levels from 0.10 kU/L to 100 kU/L. This measurement can then be used to determine your level of response to peanut allergens: [5]

• 0.35 kU/L and lower – Peanut allergy is highly unlikely.
• 0.35-0.69 kU/L – There’s a slight possibility that you have a peanut allergy.
• 0.70-3.49 kU/L – There’s a slightly higher possibility that you have a peanut allergy.
• 3.50-17.49 kU/L – There’s a good chance you have a peanut butter allergy.
• 17.50-49.99 kU/L – A peanut allergy is very likely.
• 50.00-100.00 kU/L – A peanut allergy is exceedingly likely.

To sum up: the higher your IgE count, the likelier it is that you have a peanut allergy. That said, your IgE levels can only let you know that you might have a peanut allergy. It’s up to your healthcare provider to make a full diagnosis.

Preparing for an at-home test

Preparing for an at-home test is a relatively straightforward process. All you need to do is follow the steps below to ensure your at-home test goes smoother than the creamiest hazelnut butter.

1. Monitor your symptoms

Monitoring your allergy symptoms is the first step in preparing for your at-home test. That way, you can be sure a food allergy test is warranted.

Tell-tale signs of peanut allergies include: [6]

• Hives and other skin reactions
• Redness
• Swelling
• Loss of breath
• Stomach cramps
• Itching in the throat
• Tightening of the airways
• Shock
• Dizziness

If, after being exposed to peanuts, one or more of these allergy symptoms appear, you should take a food allergy test.

You should also take a peanut allergy test even if you suspect you have a peanut allergy. You don’t want to wait until you have a potentially life-threatening reaction to learn you have a peanut allergy.

2. Understand how your test works

We’ve already provided an overview of how at-home tests work, but you should still read the directions for your specific test. That’s because some tests may differ in terms of sample collection methods and other procedures.

You should also note all components included in your kit. Here are several common test kit components:

• Blood sample collection device – While some kits may provide a vial for you to collect your blood sample, other kits may provide a collection card.
• Lancets – Lancets are small devices that allow you to easily draw blood. They typically look like push pins and are made for convenient disposal.
• Alcohol pad – Most kits provide you with an alcohol pad to disinfect the area in which you will draw blood.
• Bandages and gauze – After drawing your blood, you’ll want to quickly cover the collection area with a bandage and gauze.
• Biohazard bag – Many kits provide you with a biohazard bag designed to keep your sample safe.

If you’re using an at-home lab test, your kit also likely includes a prepaid return shipping label. This makes it easy to get your sample where it needs to go.

3. Increase your blood flow

Increasing your blood flow is not only vital for a successful workout, but also for a successful at-home food allergy test.

That’s because an increased blood flow allows you to collect the right sample amount for analysis.

To increase your blood flow before taking your test, do the following:

• Run your hands under warm water – In addition to cleaning your hands, warm water opens up your blood vessels, allowing for better circulation.
• Perform light exercise – Lightly running in place or performing some jumping jacks is a fantastic way to elevate your blood flow.
• Rub your hands together – Similar to running your hands under warm water, rubbing your hands together warms your hands and increases your blood flow.

4. Disinfect your finger and collection area

Properly disinfecting your finger and collection area helps ensure an uncontaminated sample. To sanitize your finger and collection area, do the following:

• Wipe down the area where you’ll be collecting your sample
• Wash your hands with soap and warm water
• Dry your hands and wipe your finger with the provided alcohol pad

Proper sanitation also means cleaning your area post sample collection.

Everlywell: peanut allergy testing made easy

From spicy Thai dishes to good old-fashioned peanut butter and jelly sandwiches, many delicious foods and products contain peanuts. But if you have a peanut allergy, they shouldn’t be found in you. Knowing if you have a peanut allergy is thus essential to maintaining your health.

That’s why we’re here.

Designed for people who’ve experienced mild food reactions or have a family history of food allergies, our Food Allergy Test looks for nine IgE antibodies linked to common food allergies. All you need to do is prick your finger, send us your sample, and let us take it from there.

From the first prick to the final action plan, we’ll be with you every step of the way.

Related content

How to test for food allergy: here's what you need to know

3 causes of peanut allergy

Peanut allergy symptoms explained

References

1. The Food Allergy Epidemic. Food Allergy Research and Education. URL. Accessed August 1, 2022.
2. History of food allergy. Chemical Immunology and Allergy. URL. Accessed August 1, 2022.
3. Food allergy vs food intolerance. Mayo Clinic. URL. Accessed August 1, 2022.
4. Study: Peanut-Specific IgE B Cells Reveal Their Mysteries. Food Allergy Research and Education. URL. Accessed August 1, 2022.
5. Peanut allergy. Mayo Clinic. URL. Accessed August 1, 2022.
6. How to Interpret Your Food Allergy Test Results. Oak Brook Allergists. URL. Accessed August 1, 2022.