There are three main steps to OIT. The first is an escalation phase where a small amount of protein is ingested and an increasing dose is given every 15 to 20 minutes over a period of 4 to 6 hours while being monitored in the office. The highest tolerated dose is ingested at home every 24 hours following that visit.
The next step is the build-up phase where an increased dose of protein is administered in the office once every 1 to 2 weeks. This phase takes approximately 6 months but may be longer.
The last step of this phase is to challenge to a larger amount of protein and following this, the patient enters the maintenance phase. During this last phase a daily dose is taken at home to maintain protection. In many cases the patient may freely eat the allergenic food on a regular basis if desired.
The process of OIT involves the ingestion of foods to which you/your child are allergic. As such, there is a risk of allergic reactions which could occur with either the in-office doses or home doses. Most allergic reactions that occur are mild. Mild allergic reactions may include itching of the throat or mouth, upset stomach/nausea, heart burn. Serious allergic reactions are rare but could include anaphylaxis (a potentially life-threatening allergic reaction), hives, swelling, vomiting or diarrhea, difficulty breathing, loss of consciousness, and shock, which may require emergency treatment and hospitalization. If an allergic reaction were to occur, the dose will be adjusted based on the severity of the reaction. Some patients may not be able to tolerate the OIT due to severe or recurrent reactions.
Another potential risk of OIT is Eosinophilic Esophagitis (EoE), or, allergic inflammation of the esophagus which may develop in about 7% of patients. In patients that develop EoE, the dose is typically reduced. In some cases, OIT may need to be stopped.
OIT has a significant impact on quality of life. This encompasses the emotional and social impact regarding foods eaten and improvement in the anxiety that is significant part of a food allergy diagnosis. At the “bite proof” dose, patients’ dietary restriction on foods labeled as “may contain...” or “manufacture in a facility…” can be lifted. Escalation to higher doses even allows patients to freely eat the food for which they are being treated.
Doses should never be given on an empty stomach. A carbohydrate rich meal prior to all doses is preferred.
A probiotic (such as Florajen) will be started prior to OIT.
Patients must be observed for 30-60 minutes after ingesting their home dose.
Two Epinephrine injectors must be available at all times.
The same caregivers, educated on procedure and risks, should be administering the home doses.
Exercise restriction after all doses: 2 hours following ingestion of home dose; 3 hours after in-office dose escalation.
Ambient temperature restriction following ingestion.
Asthma/allergic rhinitis must be fully controlled.
Some females may need to reduce or stop temporarily during menstrual periods.
During infections (such as upper respiratory infections, fevers, diarrhea / vomiting) doses may need to be reduced or held temporarily.
Continue to avoid food allergen other than the treatment dose.
Home dosing should not be done on the day of an OIT follow-up visit.