Oral Immunotherapy 101: Learning Module
Are your child’s food allergy or allergies impacting their quality of life? Oral immunotherapy may be able to help.
Oral immunotherapy, or OIT, helps desensitize patients to the very foods they are allergic to by giving them small quantities of the food allergen to ingest every day and gradually building their body’s resistance to the food. This treatment is now offered at Children’s Hospital of Philadelphia, in partnership with the Food Allergy Center.
To learn more about oral immunotherapy, see if your child may be a candidate and what to expect, start the module below.
Oral Immunotherapy 101
Learn what oral immunotherapy is, how it works and how it has impacted the lives of other children with serious food allergies.
Summary of the OIT Module
What is Oral Immunotherapy?
Oral immunotherapy, or OIT, helps desensitize patients to the foods they are allergic to by giving them small quantities of the food allergen to ingest every day and gradually building their body’s resistance to the food. Initial dosing and increased dosing (known as “updosing”) are completed under medical supervision at Children’s Hospital of Philadelphia (CHOP).
Patients then continue their dose every day at home for at least two weeks before returning to CHOP for an increased dose of the OIT. This process is repeated – with the patient ingesting larger amounts of the food allergen – until the child can safely ingest a specific quantity of the allergen (i.e., 1 peanut, ½ an egg, 1 ounce of milk, etc.) This is referred to as “maintenance.”
OIT goals and benefits
The goal of oral immunotherapy is for your child to reach a maintenance dose of their allergen and continue to ingest that every day for at least one year. Then, based on your child’s progress, they may be offered the opportunity to increase their daily dose. For certain foods, after about three years, the clinical team will determine if your child can reduce the frequency the allergen is ingested.
The benefit of OIT is that it can help desensitize your child to their specific allergens and prevent a severe allergic reaction in the event of an accidental exposure or cross-contamination.
For some OIT foods, our team will provide your family with dosing supplies; for others you will be instructed to provide the appropriate items ahead of your child’s scheduled visit and continue maintenance dosing at home until your child’s next visit.
Who’s eligible to receive oral immunotherapy?
To be eligible for oral immunotherapy at CHOP, your child typically must be:
- A current patient of CHOP’s Food Allergy Program in the Division of Allergy and Immunology
- Demonstrate allergy to at least one food allergen through a positive skin test, blood test and/or food challenge
- In good general health
Patients with chronic illnesses, like asthma or allergic rhinitis, may participate in OIT if their symptoms are under good control. Patients with eosinophilic esophagitis (EoE) are typically not eligible but may be considered on a case-by-case basis.
NOTE: If your child has recently had a severe reaction to any food, such as a loss of consciousness or drop in blood pressure, they cannot participate in OIT. Please discuss other treatment options with your primary allergist. We have a robust clinical research program that may offer some additional treatment options still in clinical trials. Ask your current allergist about enrollment or email FoodAllergyResearch@chop.edu.
If your child is not currently a patient at CHOP, you can request a routine allergy appointment by calling 215-590-2549. Depending on your child’s insurance, you may need a referral from your child’s primary physician.
What food allergies can OIT be used for?
At this time, CHOP offers oral immunotherapy for most common food allergens and can tailor a plan to meet your child’s needs.
Is there a limit on how many foods my child can receive OIT for?
Yes. Most children may receive OIT for up to five foods at a time. After discussing your child’s allergy history and reviewing skin and blood tests for each food allergen your child has, our OIT providers will determine which foods – and in what order – OIT is recommended for your child.
Are there age requirements for OIT?
Oral immunotherapy may be recommended for teens and young adults aged 14 to 24, however in some cases, infants and young children may also be considered.
If your young child is allergic to multiple foods, your child’s clinical team will work with your family to determine which food to trial first and when to begin OIT.
Weighing the benefits and risks of OIT
Oral immunotherapy is successful for about 80% of people; meaning that they can reach maintenance dosing of their food allergen within about six months (or longer for multiple allergens) and are safer from accidental exposures of their allergen.
However, OIT does not work for everyone. OIT team members will closely monitor your child during initial dosing and increased dosing for adverse reactions. Our team is also available if your child experiences any side effects while at home.
The most common side effects of oral immunotherapy are abdominal pain, nausea and vomiting. While most side effects are temporary, our OIT team will work with your family to develop a personalized therapeutic plan to help your child deal with any symptoms that may occur. Severe reactions, like anaphylaxis, can occur in about 10 percent of patients on OIT.
In addition, some children undergoing OIT may experience an itchy mouth or throat. We encourage many of our patients to continue taking their antihistamines (such as Zyrtec®) during updosing to decrease this risk. Talk to an OIT staff member about which medications to take or discontinue before starting oral immunotherapy or updosing.
Some patients will continue to have symptoms despite interventions. About 15% of patients stop OIT because of ongoing stomach issues or vomiting, while 5% will halt OIT due to severe allergic reactions.
OIT fundamentals for families: A step-by-step guide
To participate in OIT at CHOP, you must agree to the following:
- An intake visit, to evaluate your child’s food allergy history and determine a care plan.
- Food challenges, based on your child’s allergy history if not completed during the past year at CHOP’s Philadelphia Campus.
- Initial OIT dosing at CHOP’s Philadelphia or King of Prussia campus, so the full OIT team of clinicians can monitor your child’s reaction.
- Updosing at CHOP’s Philadelphia Campus or CHOP Specialty Care sites (with allergy specialists) as your child ingests increasingly larger controlled portions of their allergen. Specialty Care sites are an option based on your child’s progress in OIT.
- Home dosing of oral immunotherapy every day between updosing appointments.
- Maintenance dose visits to the Oral Immunotherapy Program every three to six months for up to 3 years after your child has reached maintenance dosing.
- Contact us if your child has a severe adverse reaction at any point during OIT, maintenance dosing or after.
What happens during the oral immunotherapy intake visit?
If you believe your child may benefit from oral immunotherapy, talk to your allergy provider and view our Oral Immunotherapy Fundamentals for Families. We’ve included key information within this learning module.
During your child’s initial OIT visit, our team of allergists, nurse practitioners and nurses will work with your family to determine if OIT is available and recommended for your child. We will:
- Review your child’s medical history
- Perform allergy testing on your child (skin and/or blood testing)
- Review the OIT Program goals and requirements with your family
- Seek your consent to proceed
Will my child need to undergo testing before OIT?
Before we can begin oral immunotherapy, we need to understand your child’s level of sensitivity to their allergens. Based on our initial assessment, we will recommend your child complete either:
- An OIT initiation challenge, or
- A regular food challenge to specific foods.
A food challenge is a definitive procedure for testing whether someone can tolerate a specific food. During the challenge, your child is given increasing larger amounts of the food in question and monitored closely for a reaction. All food challenge testing is completed at CHOP’s Philadelphia Campus. To learn more, see our Food Challenge Testing: Learning Module.
OIT initiation challenges are different than regular food challenges in that:
- Regular food challenges determine if your child is still allergic to a specific food or not.
- OIT initiation challenges start with small doses of the food your child is allergic to – typically 1 or 2 mg. – then your child is monitored for any reaction.
Before an OIT challenge, your child should:
- Take antihistamines as recommended by your child’s clinical team
- Eat a typical breakfast
Initial OIT dosing: when, where and how much
Your child will return to CHOP’s Philadelphia or King of Prussia campus within 2 weeks of their OIT initiation challenge for their first dose of OIT. Most children begin OIT with the first dose on our protocol for just one of their food allergies. Children can receive OIT for up to five foods at a time, but initial dosing is staggered so we can monitor reactions and adjust plans if needed.
Because the amounts are so small at the beginning of OIT, the allergen is often mixed in with another food the child safely enjoys or tolerates – such as apple sauce. This has two benefits; it helps the child ingest their allergen and it associates the allergen with a food your child already enjoys.
Your child will be carefully monitored by medical professionals for at least an hour after any OIT updosing. Severe adverse reactions are rare; however, some children may experience minor discomfort (such as mouth itching or mild abdominal pain). Clinical team members will be nearby if your child has any concerning reactions, or you have questions. Parents/guardians must stay with their child during all OIT visits.
After initial monitoring in clinic, your child will return home. Your child is encouraged to take it easy for two hours after dosing each day – no strenuous activities, exercise or extremely hot showers as these may provoke symptoms from the OIT.
For the next two weeks (or longer if needed for scheduling or other reasons), your child will continue to take OIT at home at the same dosage that was safely tolerated at CHOP. This helps your child’s body build a tolerance to the allergen.
If, at any time, your child experiences a significant reaction to OIT, you should follow your child’s anaphylaxis plan, which is reviewed regularly with OIT families.
At this time, initial OIT dosing is only offered at CHOP’s Philadelphia and King of Prussia campuses, where we have immediate access to emergency services and treatment your child may need. Subsequent updosing may be offered at a CHOP Specialty Care Center with allergy specialists, depending on your child’s progress with OIT. Virtual visits are not offered for OIT updosing.
Updosing: When, where and how often?
Once your child has been able to ingest a small amount of their food allergen, the OIT team will plan to gradually increase the dosage until your child reaches “maintenance” dosing. In most cases, the amount of allergen is doubled every two weeks to gradually build up their ability to tolerate the food.
At each updosing visit, we will:
- Evaluate your child’s vital signs
- Review any medical events that occurred since your child’s last OIT visit
- Perform a full physical exam
In addition, spirometry or peak flow measurements may be taken to assess your child’s lung function.
It is important that your child is healthy at every OIT updosing visit. If your child is sick, please call to reschedule their appointment, and ask to speak with a member of the OIT team who will guide your child’s dosing.
If your child misses a dose of OIT – for any reason – they risk decreasing their tolerance of the allergen, putting them at risk for an allergic reaction. Please call the OIT team BEFORE your child’s next scheduled dose. The OIT team will advise you about the best course of action.
Between updosing appointments
Once your child tolerates an increased dosage of OIT under supervision at CHOP, they will return home. Your child must ingest the newest dosage of OIT every day until their next scheduled visit, generally in about two weeks.
It’s important to take the OIT dose around the same time every day – ideally when the child will be home with a parent/guardian for two hours after dosing, such as after school or after dinner.
OIT dosing should be taken on a full stomach, and no exercise should be performed for 30 minutes prior to the dose and two hours after dosing. Light activities such as reading, homework, crafts, drawing/coloring, etc. are encouraged instead during this time.
Maintenance dosing: What happens next?
Once your child reaches OIT maintenance dosing – meaning they can safely ingest a pre-determined amount of their food allergen daily without a significant reaction – they will continue OIT at home for 1 to 3 years. The OIT team will then determine how much and how often to ingest the allergen.
During this time, it’s still possible for your child to have an accidental exposure to their allergen in the community or an adverse reaction to OIT. In either case, get help immediately and contact CHOP’s Oral Immunotherapy Program about possible next steps.
Adverse reactions during OIT
- Anaphylaxis can occur in about 5% of OIT patients. However, the chance of an adverse reaction is greatly reduced when patients and families adhere to instructions by OIT staff including:
Carry epinephrine all times.
Eat a meal BEFORE taking the OIT dose.
For 30 minutes before and two hours after dosing:
Refrain from vigorous activity, such as sports or exercising.
Avoid hot showers.
Certain medications, such as ibuprofen, are discouraged.
- Continue reading food labels to avoid food allergens outside of OIT dosing.
- Alcohol consumption and illicit drug use are strictly prohibited for all OIT patients.
- Call the Allergy Program at 215-590-2549 in the event of illness or any missed doses so the clinical team can determine a safe dosing plan going forward.
Maintenance dosing and therapy
Typically, a child will need at least 10 OIT office visits (at least two weeks apart) to reach a maintenance dose. For children only receiving OIT for one food, maintenance dosing may be reached within six months.
For children receiving OIT for multiple foods, maintenance dosing timelines will vary because not all foods can be started at the same time, i.e., OIT for one food may start in January and reach maintenance dosing by June; while OIT for a second food may start in February and reach maintenance dosing in July, etc. This staggered approach to dosing helps a child’s body become slowly desensitized to each food and helps clinicians identify any issues that may develop.
Once your child reaches maintenance dosing for a food, they will need to continue taking the dose for at least one year and perhaps longer.
Maintenance dosing for each child varies depending on their food allergen. Some typical maintenance dosages include:
- 1 peanut
- 1 tree nut (cashew, almond, walnut and/or hazelnut)
Your child’s doctor will let you know what the recommended daily maintenance dosages are for your child and can estimate how long it will take for your child to reach maintenance dosing for all OIT-trialed foods.
What happens during maintenance therapy?
Once your child has reached maintenance dosing, they will return to the Oral Immunotherapy Program for a visit every three months for a year. After a year of maintenance dosing, your child will be offered an OIT milestone food challenge to determine how much of the allergen your child can safely consume without symptoms.
Most patients will need to continue OIT maintenance dosing for at least three years to maintain their desensitization.
What should you expect after oral immunotherapy?
Your child will continue to follow up with their primary allergist long term to monitor for any allergic reactions. If your child has multiple food allergies and you’d like to try OIT for additional allergens, please consult with your child’s allergist and, if appropriate, make an appointment with the Oral Immunotherapy Program.
OIT concerns? How to get help
Thank you for completing the Oral Immunotherapy educational module.
We hope you feel better prepared for your child’s oral immunotherapy appointment.