Oral immunotherapy is a treatment protocol that’s used for food allergies. It involves slowly consuming higher doses of a specific food allergen over time. While not suitable for everyone, research shows it may be helpful for some types of food allergies.

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A food allergy happens when your body’s immune system mistakenly reacts to certain proteins (allergens) in food as if they were harmful substances (like viruses or bacteria) that cause disease.

The main treatment for food allergies is typically to avoid the food that you’re allergic to. However, another type of treatment called oral immunotherapy aims to boost your tolerance by slowly increasing your exposure to an allergen over time.

This article will take a closer look at the use of oral immunotherapy for food allergies, which food allergies it’s used for, and who’s a good candidate for this type of therapy.

Oral immunotherapy is a type of food allergy treatment where a person is given increasing amounts of an allergen over time. After this “building up” phase, a set maintenance dose of the allergen is taken.

For example, if you’re allergic to milk, an allergist will start by having you eat a tiny amount of milk allergen that doesn’t cause an allergic reaction. As your treatment continues, the amount of milk allergen you’re given gradually increases.

After you can consume a certain amount of milk allergen without a reaction, you’ll start with maintenance dosing. During this time, you’ll consume a set amount of milk allergen daily. This helps to maintain your response to oral immunotherapy.

The goal of oral immunotherapy is to increase the amount of exposure that leads to a reaction. The goal is not to “cure” you of the allergy, but to desensitize you to the food that causes an allergic reaction. Because some allergic reactions can be serious or life threatening, having this tolerance can protect you if you accidentally consume food that you have an allergy to.

Oral immunotherapy is typically done in an allergist’s office, clinic, or hospital under close supervision. According to the American Academy of Allergy, Asthma, and Immunology (AAAAI), the buildup phase of oral immunotherapy is given over a period of months.

According to the Food and Drug Administration (FDA), there are eight major food allergens:

  • peanuts
  • tree nuts
  • shellfish
  • fish
  • milk
  • eggs
  • wheat
  • soybeans

A 2022 review notes that the bulk of oral immunotherapy research and use is related to allergies to peanuts, milk, or eggs. Less information is available for oral immunotherapy for other food allergies, such as those to tree nuts and wheat.

According to the AAAAI, some allergists use commercial food products for oral immunotherapy. However, these treatment regimens are not FDA-approved.

In the United States, there’s currently one FDA-approved type of oral immunotherapy. It’s called Palforzia and it’s been approved for treating peanut allergy in children ages 4 to 17 years.

It’s estimated that 2.2% of children in the U.S. have a peanut allergy. While many children outgrow other food allergies, such as those to milk and eggs, only about 1 in 5 children outgrow a peanut allergy.

How does Palforzia treatment work?

Palforzia is a peanut-derived powder that can be mixed into soft foods like applesauce, yogurt, or pudding. It’s used along with a peanut-avoidant diet. Treatment consists of three phases:

  • Initial dose escalation: The initial dose escalation phase is given over the course of 1 day. It consists of five dose increases separated by about 20 to 30 minutes each.
  • Up-dosing: The up-dosing phase includes 11 dose increases that happen over a period of several months. Typically, you take each new dose daily for 2 weeks before increasing to the next one.
  • Maintenance: The maintenance phase involves taking a set daily dose of Palforzia. You must continue taking the maintenance dose in order for Palforzia to be effective.

Serious allergic reactions can happen in response to Palforzia. As such, any dose increase is given under the supervision of a healthcare professional who can manage any serious allergic reactions, should they occur.

Candidates for oral immunotherapy are people who have a confirmed allergy to a specific food. Food allergies are typically diagnosed using medical history as well as skin or blood tests.

People who already have a history of life threatening anaphylaxis (severe, life threatening reaction) to a food allergen may not be good candidates for oral immunotherapy. While this treatment approach aims to prevent these reactions, the risks of oral immunotherapy in this situation may outweigh its potential benefits.

Additionally, a 2021 review notes that research has indicated that oral immunotherapy may be more effective in younger age groups, as opposed to adults. Indeed, Palforzia is only approved for use in children at this time.

Oral immunotherapy is a long-term treatment that requires you to take a dose daily as well as keep up with any dose increases. As such, you must be willing to commit and stick to oral immunotherapy therapy for it to be effective.

Oral immunotherapy can be effective for many people. The effectiveness of oral immunotherapy often refers to achieving desensitization. This means you’ve increased the level of food allergen that you can consume without having an allergic reaction.

A rarer outcome is sustained unresponsiveness. This is when previously desensitized people can safely consume a food allergen without having an allergic reaction, even after going off maintenance dosing.

A 2022 review notes that previous research has found that oral immunotherapy can lead to desensitization to food allergens like peanuts, milk, or eggs in 76.9% of people. Most of this research has been on children.

However, there are still knowledge gaps in what we know about oral immunotherapy’s effectiveness. This includes the long-term effectiveness of oral immunotherapy as well as when maintenance dosing should be stopped.

What has research shown regarding oral immunotherapy for peanut allergy?

A clinical trial of Palforzia included 496 children with severe peanut allergies. After the initial dose escalation and up-dosing phases of treatment, maintenance doses were taken for 24 weeks.

At the end of the trial, 67.2% of children who used Palforzia could consume 600 milligrams or more of peanut allergen with only mild symptoms. Only 4% of children who were given a placebo could do the same.

Another trial of peanut oral immunotherapy included children ages 1 to 3 years. It found that 71% of children were desensitized to peanut allergens at the end of the treatment period, compared to 2% of those who were given a placebo.

This effect wasn’t maintained for all children. In the second part of the trial, children stopped treatment and avoided peanuts for 6 months. At the end of this period, 21% of children who had had oral immunotherapy could still eat peanuts without a reaction.

However, this is still much higher than the placebo group. Only 2% of children in this group had sustained unresponsiveness.

According to this research, peanut oral immunotherapy was associated with increased levels of desensitization and sustained unresponsiveness in children.

The major risk of oral immunotherapy is a severe allergic reaction called anaphylaxis. This typically happens shortly after exposure to an allergen and can include symptoms like:

The risk of anaphylaxis is one of the reasons that oral immunotherapy treatments are only done under the supervision of a healthcare professional. An allergic reaction is treated using injectable epinephrine.

It’s also important to note that anaphylaxis can occur at any point during oral immunotherapy. Because of this, people being treated with oral immunotherapy need to be able to recognize the symptoms of anaphylaxis and have their epinephrine injector handy at all times.

Other potential side effects of oral immunotherapy include:

Oral immunotherapy doesn’t cure food allergies. Instead, it can help to reduce the severity of an allergic reaction, should you accidentally eat a food that you’re allergic to. As such, it can boost the quality of life for people with food allergies.

While many people respond in some way to oral immunotherapy, not everyone will. A 2022 review notes that existing oral immunotherapy treatment protocols aren’t effective in about 20% of people. There’s also much we don’t know about oral immunotherapy.

Before starting oral immunotherapy, it’s important to have an open conversation with your doctor. Be sure to cover topics like whether you’re a good candidate for oral immunotherapy, the commitment required for oral immunotherapy, and its potential benefits and risks.

Oral immunotherapy is a treatment for food allergies. It involves slowly consuming increasing doses of a specific food allergen over time. While some allergists may use commercial food products for oral immunotherapy, there’s only one FDA-approved oral immunotherapy treatment, Palforzia.

The goal of oral immunotherapy is to increase the amount of an allergen that you need to be exposed to have an allergic reaction. This is called desensitization and can help protect you if you accidentally eat a food that you’re allergic to.

Oral immunotherapy can be effective for some people, particularly children. However, not everyone will respond to oral immunotherapy. If you or your child has food allergies, talk with your doctor about oral immunotherapy. They can give you a better idea of what it entails and if it’s recommended for your specific situation.