ALLERGIES Food Allergy

Onion Allergy Symptoms – Causes, Diagnosis, and Treatment

Onion Allergy

Onion allergy symptoms are induced by consuming or having direct contact with onions. Allergy to onion is a true allergy that is expectational. Studies exhibit that only 3% of adults could possibly have this allergy.

Despite the figures, there’s a significant amount of people battling onion intolerance. People with onion allergies don’t show as many negative reactions compared to others.

Moreover, individuals with onion intolerance can eat small amounts of cooked onion. Whereas some of those having the allergy can’t even stand the odor of onions.

In most situations, raw onion is the reason for the allergic reaction. However, onion arrives from a large collection of vegetables called the allium family. It’s genuinely hard to avoid. We use onions for cooking, seasoning, and preserving different types of foods.

Onion Allergy Symptoms

Allergic reactions to onions or onion allergy symptoms can be interior or external. External reactions often result from getting in touch with or smelling onions. While internal reactions come from taking in onions.

An individual’s reaction or allergic reaction can appear at different times and at different degrees. Some people have instant reactions, while other people don’t show symptoms for at least 24 hours. The stage of their allergic reaction relies on how hypersensitive they are to onions.

As for the treatment time, most patients feel better as soon as the allergen is removed from their bodies. There are unusual cases though. Where the allergic reaction persists for days, even right after the onion has been out of the system. With in onion allergy person can experience allergic symptoms like:

  • Itching eyes, lips, throat, and different part of body
  • Rashes or dry skin flakes
  • Fatigue, Nausea, Diarrhea, and hives
  • Mental disorientation
  • Swelling of lips and different body parts
  • Puffy eyes and face
  • Fainting
  • Stomach Pain
  • Tongue, Mouth, and Gum blisters
  • Reflux Esophagitis
  • Difficulty Breathing and Asthma
  • Anaphylactic shock
A girl suffering from onion allergy, abdominal pain, colon problems, gastritis, or diarrhea.

What Causes an Allergy to Onions?

The causes of the onion allergy symptoms are the same as the other food allergies like coffee allergy and coconut allergy. When you take raw onions or a food that contains onions, the immune system of the body responds negatively to it.

The immune system of the body shows that the protein of this vegetable will cause harm to the body. To destroy this protein. The immune system immediately produces antibodies such as IgE which tackles the protein.

The protein and IgE battle against each other and because of this the body produces Histamine. Particularly, from the gut or skin for the benefit of the safety of the body.

The chemical Histamine is developed in an excessive manner than needed. It reacts adversely to the body and this results in allergy to induce. The time to start reaction will vary with the patient’s level of sensitivity to the onion and the amount of intake.

Normally, it can extend from a few minutes to an hour to exhibit its impact on the body. Sometimes individuals can’t realize whether it is the allergy to onions or other things.

If you are doubtful, avoid foods that include onions for a few days and check out what is the result. If any adverse reaction does not occur. Then, it is confirmed that it was onions that were liable for those annoying moments.

Onion Allergy or Intolerance?

The symptoms and indications of allergy and food intolerance are almost identical. It makes people puzzled or confused to differentiate them. The onion allergy responds very quickly. It can start within a minute after eating onions.

The response can be very serious and life-threatening. But with onion intolerance, it can take as much as a day for the symptoms to show up and the reaction is moderate. Food that can cause onion allergies include:

  • Garlic chives
  • Broth or stock
  • Pre-made pizza crusts
  • Flavored cheese, especially Mexican cheese
  • Onion juice and Onion powder
  • Scallions
  • Garlic and Garlic powder
  • Premade soups and sauces
  • Shallots
  • Saltine crackers, unless specified otherwise
  • Frozen chicken and turkey
  • Most processed or canned meat, unless specified otherwise
A macro close up image of green onion slices

Plants related to the Lily family may also lead to onion allergy. It would be best to stay away from the sap of the following:

  • Tulips
  • Agapanthus
  • Iris
  • Daffodils
  • All types of Lilies
  • Alstroemeria

Diagnosis and Testing

Your first concern is to seek medical advice from an allergist and examine yourself. They should be able to validate your allergy and recommend some medications. In case you are allergic to onion, you need to be aware of cross-reactivity from other food and plants. Common ways to diagnose allergy:

  • Patch test or Skin Test
  • Elimination of onion-containing diet. A patient is advised to carefully observe his diet while removing food items. The allergist will ask the sufferers to avoid onions for a period of time. If the symptoms stop existing, then allergist can diagnose allergy.
  • An allergist can perform a blood test, a particular IgE blood. It helps to figure out if a person is struggling from onion allergy or just hypersensitivity.

Onion Allergy Treatment

  • If you only have an onion allergy, antihistamines may not perform well for you. If that’s the scenario, it’s best to just wait for the onion to be eliminated from your body.
  • Eating almonds can aid neutralize the acids in your stomach. Therefore, reducing the flow back and hurt burn symptoms from onion intolerance.
  • Aloe Vera can be slathered over inflammation, burning, or scratchy parts of the body. It will give a comforting effect that will reduce the symptoms.
  • Bananas helps to digest certain foods and help to relieve the sensation of swelling. Are you allergic to bananas?
  • Epi-pen should be maintained by anyone who encounters strong allergic reactions to the onion. People who undergo anaphylactic shock should also have this for urgent situations.
  • Albuterol inhalers are excellent for those who experience respiration complications and asthma attacks when their allergy is induced.
  • External creams, ointments, and corticosteroids- can aid relieve cities and other skin reactions. Nix Vomica is a natural, homeopathic remedy. It can comfort digestive problems triggered by onion allergy.


  • Don’t consume onions and garlic because they belong to the same lily family. Even if your body could handle cooked onions. It’s best to avoid the allergy-causing agent to stay away from any adverse reactions.
  • Always read food labeling or ingredient lists if you are allergic to onions. Make sure to examine everything. Watch out for terms like “herbs”, “spices” and “natural flavorings”. These terms are usually used when an item was flavored with onions and a variety of other seasonings.
  • Avoid eating at restaurants because they include onions garlic. You can’t be entirely safe even if the server informs you that the dish is free from onions. Possibilities are the already produced salsas or seasonings utilized for the dish have onions in them.
  • Stay away from foods that are in the same family group as onions.