This section is intended for those who have probably researched this treatment and wish to become familiar with how OIT is done at our office.
Oral immunotherapy is in fact quite like any other desensitization treatment in allergy. The oral route currently appears to be the most effective to treat food allergies, whereas similar strategies for airborne allergens (pollens, pet dander, etc) and insect venom give best results by injection.
Is oral immunotherapy experimental? Dr Morgan has offered this treatment to many patients since the mid-2000s. At the time, very few allergy specialists offered this treatment, but by now a gradually increasing number of allergy specialists are starting to offer OIT. The first pharmaceutical food (peanut) to be used for treatment became available in 2020. While oral immunotherapy is not offered by the majority of allergy specialists, this does not make it experimental! Over that time period, concurrent treatment of multiple foods, non-daily maintenance dosing, and remote supervision have been successive innovations to improve the flexibility and appeal of OIT for patients.
Similar to other immunotherapy, OIT is able to reverse the underlying abnormality in the immune system that causes food allergies. Still, OIT is not always a true cure. In fact, before starting OIT, patients must spend all their energy trying to avoid foods that cause allergic reactions. The complete opposite is true after finishing OIT. Now, patients must be careful not to forget eating the food! Most patients at our office are eventually guided to dosing the formerly allergenic food 3 to 4 days per week. This reduces the burden of needing to take the food so strictly while maintaining the desensitized state.
All common foods are possible to treat, although certain foods have their individual quirks.
Usually, there is a minimum goal in order to consider the treatment worthwhile and that would greatly diminish the risk from an accidental bite of the offending food. A more aggressive goal would allow most patients to eat the food similarly to a normal person. Most families target a higher dose that basically allows the food to be part of the diet like a normal person.
The following table reviews briefly the foods that are treated, as well as typical goals and some comments about Dr Morgan’s experience with their quirks.
| Category | Foods | Goal | Comments |
|---|---|---|---|
| Peanut | Peanut and peanut candy | 8 peanuts (minimum: 1) | Most commonly requested food to treat |
| Tree Nut | Walnut, cashew, less commonly others | 2 walnut halves, several cashews | Often treated concurrently with peanut |
| Seeds | Sesame, rarely others | Helva candy, plain tahini, etc | Protocol similar to nuts |
| Milk | Cow’s milk, rarely other milk | 1 cup milk (min: 15 mL) | Slightly longer to reach maintenance dose |
| Egg | Raw liquid hen’s egg white | Half to full egg (min: fractional egg) | Often later switched to cooked egg due to palability |
| Wheat | Multi-grain bread | Full slice of multi-grain bread (min: partial) | Wheat, barley, rye are treated together |
| Other Legumes | Soy, rarely other beans | Half cup soymilk | Slightly higher success rate than cow’s milk |
| Seafood | Fish, crustacean, mollusk | Highly individualized | Not popular due to need for regular maintenance ingestion |
| Low Protein | Fruits, vegetables, others | Highly individualized | “Exotic” (rarely allergenic) foods can need treatment too! |
Basically, OIT involves an initial long day spent in the office. Starting with a very small dose, every 30 min a new, higher dose is ingested. The goal is to reach a small dose that can be easily measured and taken at home. This is a one-time procedure that can be any day Monday through Thursday.
The rest of the dose increases occur more gradually: every 2 weeks or so, although highly motivated families who are tolerating the treatment can come every week. Usually, there are at least a dozen of these visits. There is a mandatory wait of at least 30 minutes ingesting the dose in the office, except for a pharmaceuticalized food, for which a 1 hour wait is required.
Prior to 2020, few patients opted for remote dose increases done at home via video conferencing with Dr Morgan. Mainly, this was due to poor support by health plans for telemedicine services. Comparing 2019 to the coronavirus pandemic in 2020, a small number of enthusiastic remote patients became a majority by necessity, as health plans were forced to catch up to the 21st century. Currently, patients who have done well after several office dose increases can be transitioned to home dose increases. Presence of fever, active airway allergies, or significant change in the form of food being dosed should either defer or conduct the dose increase in the office. Generally, parents can be a bit anxious with the first remote visit, whereas many children are less anxious due to being in the familiar home environment.
Patients undergoing treatment from a long distance away would also be natural candidates for telemedicine. Unless a patient resides in a jurisdiction known to be rigidly intolerant of out-of-state telemedicine, patients whose protocols are established in the office are reasonably considered to be continuing existing care regardless of the physical location during a video conference.
| Timeframe | Goal | Comments |
|---|---|---|
| Initial Consultation | Review testing; verify true allergy; plan foods to be included | Observed ingestion of foods might first be recommended for foods not certain to be true allergens |
| Rapid Desensitization Day | Increase dose from zero to practical amount that can be taken at home without needing to dilute | Multiple doses with half hour observation under close supervision |
| Every 7 to 14 Days | At least 12 additional dose increases | Same half hour observation period must be observed; after 2 or more dose increases in optimal candidates, encounters can transition to remote from home |
| After Several Months of Maintenance Dose | Observed ingestion of large amount, such as full peanut butter sandwich | If desired, supervised transition to non-daily dosing, such as 4 days per week |
Most patients who undergo OIT are children. Generally, younger children seem to have smoother courses. This might be due to lack of anxiety, more pliable immune systems, less time that the allergy has become hard wired into the immune system, and less time to have developed severe nasal allergies or asthma. While parents might be anxious as to how to tell if infants are having a reaction on treatment, this is balanced out by less risk of reaction at the youngest ages.
Exercise should be avoided at least 1 hour before and 1 hour after. Very strenuous exercise should probably observe a longer 2-hour window. For older patients, alcohol and stress/anxiety in a similar timeframe could also increase the risk of reactions, even when a dose of food was previously doing well. Active nasal problems, asthma, and other airway disorders must be tightly controlled beforehand and certainly during the protocol. In many cases, Dr Morgan is attuned to somewhat subtle airway problems that truly are not noticeable or bothersome to patients but can still threaten the success of therapy. It is advisable to go ahead with what seems like “over-treatment” during the protocol in such mild cases. Once doing well on maintenance, treatment of other allergies can sometimes be relaxed. That said, it is also true that some patients with active nasal allergies or frequent viral infections seem to be unfazed while on OIT.
A longstanding success rate quoted in many centers is 85%. This is probably about right, especially when including patients who are young adults with a bit higher risk of reactions than very young children. Of the 15% who do not achieve full success, perhaps 5% are truly resistant to the protocol. Another 5% are those unwilling or unable to achieve excellent control of nasal allergies or asthma. Perhaps the final group of 5% are successful in reaching a partial dose of the food but are unable to continue due to mild reactions or intense dislike of the taste of the food.
As with any medical protocol, OIT is not free of risk. The way to think about OIT is the risk is not eliminated but transformed. Reactions in those with untreated food allergies are unpredictable and often severe. The protocol for OIT works in such a way to introduce a food allergen gradually and carefully so that allergic reactions is unlikely. If reactions do occur under such supervised conditions, they are milder and somewhat more predictable.
| Reaction | Severity | Comments |
|---|---|---|
| Stomach | Not dangerous but can make treatment unpleasant if not managed | Often similar to upset stomach seen as a medication side effect |
| Mouth | Also not dangerous and often treated with antihistamine | Itchy mouth or throat |
| Skin | Much more limited than reactions in untreated patients | Few hives around the mouth |
| Psychological | Anxiety is not merely mental and can threaten the success of treatment | Desensitizing to food allergens must take place not only in the immune system but psychologically as well |
OIT is potentially life changing, attempting to reverse a handicap that strikes at one of the most basic human cultural activities: eating.
Please do not hesitate to contact the office to explore OIT further.
Thank you for visiting www.lasvegasallergy.com!