Food Allergy Symptoms

Written by

Lauren Dobischok
31 May, 2023

Medically checked article All HOMED-IQ content is reviewed by medical specialists

Do you frequently suffer from stomach cramps or nausea after eating certain foods? Or perhaps you break out in a rash or your mouth feels itchy after a meal? You might be one of the millions around the world living with a food allergy. Food allergies can cause a variety of symptoms, ranging from unpleasant and inconvenient to life-threatening emergencies. Read on to learn more about the most common food allergy symptoms and when to consider an allergy test like Homed-IQ’s Allergy Test Extensive

Recognising Food Allergy Symptoms

Food allergies occur when the immune system overreacts to certain types of food (Mayo Clinic). During this reaction, the immune recognises the allergen as a threat to the body, triggering a protective response that causes the symptoms of allergies. Allergic reactions can vary widely in severity and cause symptoms affecting different parts of the body. If you suspect that you have a food allergy, identifying and understanding these symptoms can be crucial for managing your condition and preventing it in the future. Below, we delve deeper into the symptoms typically associated with food allergies.

Digestive Symptoms

One of the most common signs of a food allergy is discomfort in the digestive system. This can include stomach cramps, gas, bloating, or a sensation of fullness. Some people may also experience nausea, vomiting, or diarrhea. These symptoms can occur within minutes or several hours after consuming the offending food (Mayo Clinic). Digestive food allergy symptoms can be harder to identify because they can be mistaken for indigestion, food poisoning, or other stomach ailments. Elimination diets may be used to identify an allergy that causes digestive symptoms, which involves not eating the suspected allergen for a period of time, followed by reintroducing it and checking if symptoms occur. 

Skin Reactions

Skin reactions are another easily recognisable symptom of food allergies. A common reaction is an itching or a tingling sensation in and around the mouth after eating a certain food. Redness or swelling may also occur, particularly around the mouth, face, or the area where the allergenic food made contact with your skin. Hives, characterized by red, itchy, raised welts that resemble bug bites, are also common symptoms of a food allergy (NHS, 2023). People with allergies are also at higher risk of having eczema, a skin condition that causes dry, itchy, red skin (Conaway, 2022).

Respiratory Symptoms

In some cases, food allergies can lead to respiratory issues. These may present as a runny or stuffy nose, sneezing, coughing, wheezing, or difficulty breathing. Some people may feel a tightening in their chest and throat, or a change in the sound of their voice. In extreme cases, food allergies can lead to anaphylaxis, which can restrict breathing and can be life-threatening (NHS, 2023). 

Cardiovascular Symptoms

While less common, food allergies can also affect the cardiovascular system. These symptoms include lightheadedness, fainting, a drop in blood pressure, and an irregular or increased heart rate. These signs often indicate a severe allergic reaction and should be treated as a medical emergency (NHS, 2019).


Anaphylaxis is a severe, life-threatening allergic reaction. It often occurs within minutes of exposure to the allergen, but symptoms can occur half an hour or more later. Anaphylaxis often involves multiple systems in the body, with symptoms including difficulty breathing, wheezing, dizziness, loss of consciousness, and rapid pulse (NHS, 2019). It can also cause a dramatic drop in blood pressure, leading to shock. If you experience symptoms of anaphylaxis, it is crucial to seek immediate emergency medical care. 

People who can experience anaphylaxis should always carry an epinephrine auto-injector (Epi-Pen). If symptoms of anaphylaxis occur, you should use the injector immediately. It is important to still seek medical care even if you begin to feel better, as some reactions require more than one dose of epinephrine or additional treatment (NHS, 2019).

Getting an allergy diagnosis

If you’re experiencing any of the above symptoms, it’s crucial to get an allergy test. Allergy tests are medical evaluations that determine if a person is allergic to specific allergens, including foods. By getting tested, you can identify the foods or other substances causing your reactions and learn how to manage your symptoms effectively. 

Allergy tests usually involve visiting a doctor or allergist. Common allergy tests include:

  • Skin Prick Tests: In a skin prick test, a small amount of the suspected allergen is placed on the skin, usually on the forearm, back, or finger. The skin is then lightly pricked, allowing the allergen to enter the skin’s surface. If you’re allergic to the substance, you’ll likely develop a raised bump or reaction at the test location. Skin prick tests are considered to be a highly reliable method of checking for allergies, but should be done under medical supervision in case a severe allergic reaction occurs.
  • Blood Tests: Blood tests measure the amount of specific IgE antibodies in your blood. The presence of these antibodies indicates an immune system response to a specific allergen. This type of test can be useful when skin testing is not feasible or is inconclusive. Blood allergy tests can also be done from home as there is no exposure to the allergen and therefore no risk of allergic reaction. Homed-IQ’s Allergy Test Extensive is a home test for more than 295 allergens relating to 167 specific allergies, including milk, seafood, fruits, vegetables, herbs, eggs, meat, legumes, grains, and nuts. The test can be easily completed from home before being analysed in a certified laboratory. The results are then sent to your Homed-IQ account and can be brought to your doctor for follow-up care.
  • Oral Food Challenge: An oral food challenge is considered the most accurate way to diagnose food allergies. Under medical supervision, you’ll consume a small amount of the suspected allergen, and the reaction will be observed. The amount is gradually increased unless a reaction occurs. This test is typically only done when other tests are inconclusive, as there is a risk of a severe reaction.
  • Elimination Diet: If it’s suspected that certain foods are causing an allergic reaction, your healthcare provider may recommend an elimination diet. This involves removing these foods from your diet for a few weeks and then gradually reintroducing them to observe any reactions.

Source: Cleveland Clinic, 2021

Ensuring Your Health and Wellness

If you suspect you might have a food allergy, don’t ignore your symptoms. Early identification and management are key to maintaining your health and preventing serious allergic reactions. Once an allergen is identified, you can take steps to learn how best to avoid that food and make changes in your diet in order to stay healthy and alleviate symptoms.


Cleveland Clinic. (2021, July 2). Allergy Testing.

Conaway, B. (2022, November 16). Allergies and Eczema: What’s the Link? WebMD.

Mayo Clinic. (2021, December 31). Food allergy – Symptoms and causes.

NHS. (2019, June 14). Anaphylaxis.

NHS. (2023, January 12). Food allergy.

About the author

Lauren Dobischok

Lauren is a health scientist and science communicator currently living in the Netherlands. Originally from Canada, she completed a Research Master’s in Health Sciences at the Netherlands Institute of Health Sciences at Erasmus University Rotterdam (NIHES) with a specialisation in epidemiology. Prior to her master’s degree, she completed a Bachelor’s degree in Health Sciences at Simon Fraser University. With a background in public health, her goal is to create accurate scientific content that is easy to understand and empowers people to make informed decisions. Within Homed-IQ, Lauren works as a Product Developer and Content Lead, working closely with physicians and scientists on medical devices for Homed-IQ’s new products and written communications.