Diagnosing food allergies is not as straightforward as diagnosing other conditions. As mentioned, symptoms of food allergies can vary widely from person to person, and you may not experience the same symptoms every time you react.

Food allergies don't just affect one specific part of the body. Their effects can be felt on the skin, respiratory tract, digestive system, and even the cardiovascular system. Most food allergies are evident from childhood, but some people may develop allergies at different ages.

Despite these facts, you should still consult a doctor immediately if you suspect you have an allergy. The doctor will provide treatment and information on managing allergies according to their causes.

Before undergoing various tests, you must first have a physical examination. Sometimes, allergic reactions can appear later, making it difficult to determine which food triggers the allergy.

During the physical examination, the doctor may ask about symptoms you've experienced, such as what reactions occurred, how long after eating the food they happened, how much was consumed, how often you experience reactions, and whether the reaction occurs every time you consume a specific food.

The doctor will also inquire about your and your family's medical history to determine the presence of other allergies or the possibility of inherited allergies, as well as your daily diet.

However, the history provided by patients alone cannot be a definitive measure and is often difficult to interpret. Therefore, you must undergo additional tests if it is suspected that you have an allergy.

Here are the allergy tests that may be performed to confirm a specific food allergy:

Oral Allergen Exposure Test:
In this test, the doctor will give you a small amount of food suspected of causing an allergy, possibly in capsule form. The quantity given will gradually increase. During this process, the doctor will monitor for any allergic reactions that appear. If no allergic reaction occurs during the test, then the food is considered safe and can still be included in your daily diet.

Skin Test:
Allergy skin tests are also commonly performed to diagnose food allergies. In this test, a small amount of extract from the allergenic food is placed on the skin of your back or forearm. The skin is then pricked with a needle to allow the substance from the food to enter underneath the skin. If you develop a bump or feel itching around the area that was pricked, you likely have an allergy to the substance being tested. However, the presence of a reaction is not enough to definitively confirm a food allergy.

Blood Test:
The blood test aims to detect your immune system's response to a specific food by checking for immunoglobulin E (IgE) antibodies in your blood. IgE is an antibody produced by the body when exposed to an allergen, which can lead to symptoms such as itching or stomach pain. During the test, a nurse will take a blood sample from a vein in your arm using a small needle.

Elimination Diet:
Unlike other tests, the elimination diet takes longer as it involves your daily diet. In this diet, you need to eliminate several food groups suspected of causing allergies for two to six weeks.

You do not need any special preparation before undergoing food allergy tests. Moreover, the tests cannot predict the severity of the allergies you might have. They only determine the possibility of an allergy to a particular food. This record will assist you in providing a more accurate report during a physical examination with your doctor.

Author: Dr. Fatimah Bebi – Medical Service Doctor at PRAMITA Medical Laboratory and Clinic Diponegoro Branch, Medan