Onion allergy

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When it comes to onion allergy, it is usually triggered by consuming or direct contact with onions. An actual onion allergy is considered rare. Based on studies conducted, only a small percentage of the population actually suffers from onion intolerance.

Individuals with onion intolerance do not experience adverse reactions unlike those who have the actual onion allergy. Furthermore, those who have intolerance can eat small amounts of cooked onion while those with the allergy might not even stand the smell of onions.

In most cases, raw onion is responsible for an allergic reaction. Nevertheless, onion comes from a large group of vegetables which is difficult to avoid. In addition, onions are used in cooking, flavoring and preserving various types of foods.

Foods that can cause onion allergy

  • Garlic
  • Leeks
  • Gardener’s garlic
  • Chives
  • Scallions
  • Shallots
  • Onion juice
  • Stock or broth
  • Pre-made sauces and soups
  • Frozen turkey and chicken
  • Onion powder
  • Garlic powder
  • Flavored cheese particularly Mexican cheese
  • Most processed or canned meat
  • Pre-made pizza crusts
  • Saltine crackers

Symptoms of onion allergy

Onion allergy can be external or internal. The external reactions typically occur from direct contact or smelling onions while internal reactions occur from ingestion of onions.

Onion allergy
An individual with onion allergy can experience breathing difficulty.

The response of an individual can manifest at various times and at varying degrees. Some experience an immediate reaction while others do not have any symptoms for at least 24 hours. The degree of the allergic reaction depends on how the individual is sensitive to the onions.

  • Rashes or dry skin flakes
  • Hives
  • Itchiness
  • Swelling of the lips and other parts of the body
  • Breathing difficulties
  • Bloating and gas formation
  • Asthma
  • Diarrhea
  • Fainting
  • Nausea
  • Reflux esophagitis
  • Sore throat
  • Mouth blisters
  • Puffy eyes and face
  • Blisters on the gums and tongue
  • Burning sensation in the mouth
  • Anaphylactic shock

How onion allergy is diagnosed

The priority is to consult a doctor so that proper treatment can be started. The common ways to diagnose onion allergy include the following:

  • Skin prick or patch test
  • Blood test
  • Elimination diet


  • The individual should avoid eating onions. Even if he/she can handle cooked onions, it is best to avoid the allergen.
  • Carefully read the food labels especially phrase such as “spices”, “seasonings” and “natural flavorings”.
  • If possible, avoid eating out. There is a possibility that the pre-made sauces or seasonings contain onions.

Treatment of onion allergy

  • Antihistamines work well if the individual has onion intolerance.
  • Aloe vera can be applied over burning, swollen or itchy parts of the body. It provides a soothing effect that minimizes the symptoms.
  • Almonds help neutralize the acids in the stomach, thus reducing the reflux and burning sensation.
  • Bananas promote digestion and helps relieve the bloated sensation.
  • An albuterol inhaler is suitable for those who experience breathing difficulties and asthma attacks.
  • An epinephrine auto-injector should be on hand at all times especially those who experience severe reactions.
  • Topical creams and ointments help relieve hives and other skin reactions.

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