Food allergy blood test: discover your allergens

An itchy mouth after fruit, stomach pain after milk or a swollen lip after peanuts. Symptoms like these after eating may point to a food allergy. But how do you know what you are allergic to?

An allergy blood test shows whether your immune system makes IgE antibodies to certain substances in food. This used to be called a RAST test. Today the lab measures specific IgE per allergen, which can give a first indication.

There are two kinds of allergy test: the skin prick test and the blood test. This page is about the blood test.

This test may suit you if you have symptoms and want to know which allergens could play a role. For example:

• You get itching, a rash, stomach pain or swelling shortly after eating certain foods.
• You are unsure which of several foods is causing your symptoms.
• A skin prick test is difficult for you, for instance because of eczema.
• You want to order an allergy blood test yourself, without a referral.

Food allergy panel: specific IgE antibodies to common food allergens from one blood draw. These typically include milk, egg, wheat, soy, peanut, tree nuts, fish and shellfish.

This is an extended IgE test for food. Airborne allergens such as house dust mite and pollen are in our separate inhalation test.

The result shows, per allergen, whether IgE antibodies are present in your blood and how much. Labs often report this as a class from 0 to 6.

This gives insight into which allergens your body recognises. Together with your symptoms, a doctor can assess whether an allergy may be involved.

Your blood is drawn at a collection site run by an independent, certified laboratory. We work with these labs across the Netherlands.

After your order we arrange the referral through ZorgDomein. Allow one business day. You receive an email with a barcode, which you show at the collection site. Without a BSN there is no barcode: you then print your referral form through the link in the email and bring it to the draw location.

An allergy blood test can be useful at different moments:

• Your symptoms start within a few hours of a meal and you want to know which foods are involved.
• You want to bring facts to your GP or dietitian instead of guesses.
• You already avoid certain foods and want to know whether that is necessary.
• You want a first step before seeing an allergist.

Class 0 means no IgE to that allergen was found. The higher the class, the more antibodies were measured.

IgE in your blood does not always mean you will have symptoms. Research shows that some people with a positive result have no allergy. So do not cut foods from your diet on your own.

Discuss your result with your GP or allergist. Sometimes a food challenge test is needed to confirm an allergy.

You usually do not need to fast for this IgE test. Preparing well mostly means eating as you normally do.

Do you take medication, for example for hay fever? Mention it when you order so the doctor can take it into account.

Once the lab is done, a BIG-registered doctor assesses your result. You get a notification and can read everything in your account.

You can share the result with your GP, who can help you decide whether further steps are needed.