What causes an apple allergy?

Author: Kowshik Ahmed Kafi

Food allergies occur when people eat something that causes their immune system to overreact. This overreaction can result in a variety of unpleasant and sometimes life-threatening symptoms.

For people with an apple allergy, these reactions occur after eating an apple.

Symptoms of an apple allergy

tAn apple allergy can cause symptoms when eating raw apples or apple's derived products, such as juice or puree.

People that have an apple allergy may experience a range of symptoms when eating an apple or shortly afterward. Symptoms of an apple allergy may vary based on the type of apple allergy a person has.

Symptoms include:

  • itchy throat or mouth

  • swollen lips or throat

  • stomach discomfort and cramps

  • rash or

  • hives

Types of apple allergies

People of any age, ethnicity, or gender may suffer from an apple allergy. However, the type of apple allergy a person has can vary.

There are two main types of apple allergies. In the first kind of apple allergy, people are allergic to a protein in the apple that is closely related to a protein found in peaches.

In these people, symptoms, which can be very severe, may begin almost immediately after they have eaten an apple. People in the Mediterranean are more prone to this type of apple allergy.

In the second type of apple allergy, the person may be reacting to a protein within the apple that is very similar to proteins found in birch tree pollen. This is known as cross-reactivity.

These people usually have a milder reaction, with symptoms developing in and around the mouth. This is known as oral allergy syndrome.

This type of apple allergy is more likely to affect older children and adults in cooler climates where birch trees are more prevalent. People may have more symptoms during the spring when birch pollen is in the air.

People who develop oral allergy symptoms are more likely to have hay fever and upper respiratory allergies.

What is oral allergy syndrome?

Unlike a peanut, wheat, or shellfish allergy, some allergies are caused by an allergic reaction to pollen. This reaction can cause some people to develop an itchy throat and mouth after eating certain foods, including apples that contain proteins that are very similar to pollen.

Oral allergy syndrome is sometimes referred to as pollen fruit syndrome.

Doctors generally consider oral allergy syndrome to be a mild form of food allergy that is caused by a contact allergic reaction in the mouth and throat. This means that a person with the condition reacts after their mouth touches a particular fruit, such as an apple.

People with oral allergy syndrome react to foods based on what type of seasonal allergies they have. For example, a person with an apple allergy will likely be allergic to birch pollen, which is very prevalent in the springtime.

If a person finds their seasonal allergy symptoms are worse in spring, they may be more likely to have cross-reactive oral allergy syndrome from eating apples.

Symptoms of oral allergy syndrome

An oral allergy causes symptoms in and around the mouth and throat, including itchiness and swelling.

Symptoms of oral allergy syndrome vary from person to person. Symptoms are usually mild but occasionally may be severe.

Most often, oral allergy syndrome symptoms only occur in or around the mouth. Symptoms may include any combination of the following:

  • itchy mouth or throat

  • swollen lips, mouth, or tongue

  • itchy, swollen throat

  • itchy ears

Triggers and foods to avoid

Apples are not the only food that can trigger oral allergy syndrome symptoms. Other triggers of oral allergy syndrome occur from eating foods associated with the following allergens:

  • birch pollen

  • ragweed pollen

  • grass pollen

Typical trigger foods for oral allergy syndrome include the following foods:

  • almonds

  • carrots

  • cherries

  • celery

  • peaches

  • plums

  • pears

  • melons

  • tomatoes

  • oranges

  • kiwi

  • banana

  • sunflower seeds

  • cucumbers

  • zucchini

People with an apple allergy may want to avoid these foods if they also cause a reaction.

When to see a doctor

An allergist will be able to diagnose food allergies, including apple allergies.

Anyone who experiences food allergy symptoms should consult with a doctor for a diagnosis. While doctors can check immunoglobulin E (IgE) antibodies to identify food anaphylactic risk, it may not be accurate for the diagnosis of oral allergy syndrome.

An allergist will make a diagnosis based on a variety of factors, including the history of symptoms, skin prick tests, blood tests, and oral food tests.

Anyone with an allergy should be aware of the risk of anaphylaxis, an emergency medical situation that causes the body to go into shock as a person’s blood pressure rapidly lowers and airways narrow.

A person experiencing symptoms of anaphylaxis should seek immediate medical attention, especially if they have a known allergy. Symptoms of anaphylaxis typically start right away and include:

  • difficulty breathing

  • confusion

  • wheezing

  • swollen throat and swelling in and around the mouth

  • low pulse

  • trouble swallowing

  • nausea

Treatment

In cases where an apple allergy is not severe, the best treatment for a person with an apple allergy is to avoid eating apples.

In some cases, people with oral allergy syndrome may be able to eat cooked apples, as cooking apples may alter the protein that causes the reaction. This is true of other fruits that cause oral allergy syndrome, as well.

A person who experiences an anaphylactic reaction to apples or any other substance requires emergency medical attention. Treatment for a person with a life-threatening food allergy can include:

  • immediate use of an epinephrine injection (EpiPen)

  • intravenous medications, including antihistamines and cortisone

  • oxygen and albuterol to help breathing

  • medical monitoring to ensure anaphylaxis is resolved

Outlook

Preventing contact with apples is the best treatment for people with an apple allergy. People with apple allergies will want to avoid eating raw apples and check the ingredients on other products to ensure they do not contain apples.

Some people with oral allergy syndrome may be able to eat cooked apples, but should always ensure they have been cooked for a proper amount of time.

Anyone with a severe allergy to apples should carry an EpiPen in case of an emergency.