How Food Immunotherapy (OIT & SLIT) Works to Prevent Allergic Reactions

You've heard about peanut immunotherapy, but what is food immunotherapy, actually? How do treatments like Oral Immunotherapy (OIT) and Sublingual Immunotherapy (SLIT) work, and which one might be right for your family?

In this game-changing episode of Allergy Actually, your bestie allergist moms – Dr. Kara Wada, Dr. Amber Patterson, and Dr. Meagan Shepherd – break down the two leading cutting-edge treatments for food allergies. They compare OIT (eating tiny, controlled doses of the allergen) with SLIT (placing drops under the tongue) to help you understand these life-altering therapies.

Learn about the different goals of treatment—from achieving "bite safety" against accidental exposure to reintroducing a food completely into the diet. The doctors discuss the pros, cons, risks, time commitment, and what to expect from each approach, giving you the knowledge to have an informed conversation with your allergist.

EPISODE IN A GLANCE
00:45 What is Food Immunotherapy?
01:37 OIT vs. SLIT: The Key Differences
04:00 What's Your Goal? "Bite Safety" vs. Full Reintroduction
06:24 OIT: The "Aggressive" Approach (Higher Risk, Potentially Faster)
06:36 SLIT: The "Gentle" Approach (Lower Risk, Slower Pace)

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ABOUT HOSTS
KARA WADA, MD
Dr. Kara Wada is a quadruple board-certified physician in allergy, immunology, and lifestyle medicine, and founder of the Immune Confident Institute. As a Sjogren’s patient and life coach, she combines modern medicine with lifestyle and mindset practices to help patients harness their body's ability to heal.
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AMBER PATTERSON, MD
Dr. Amber Patterson is a world-renowned allergy and immunology expert pioneering the future of immunotherapy. As the U.S. ambassador for ILIT™ Protocol (a 3-injection allergy shot protocol), she is redefining allergy care through her practice, Auni Allergy®, and the groundbreaking Auni® ILIT™ Learning Network.
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MEAGAN SHEPHERD, MD
Dr. Meagan Shepherd is a board-certified allergist and immunologist with nearly 15 years of experience specializing in advanced immunotherapy. She is known for her practical, evidence-based approach and her unique focus on "allergy-conscious living"—designing homes, habits, and lifestyles that improve her patients' quality of life.

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Transcript

Episode 16 - Food immunotherapy OIT vs SLIT
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Dr. Kara Wada: You've heard about peanut immunotherapy and maybe even seen those viral videos of kids eating a peanut for the time. But what is food immunotherapy? How does it actually work? And what's the deal with swallowing drops under your tongue instead of eating those tiny doses of allergens? Today we are tackling and talking about OIT versus SLIT to cutting edge treatments for food allergies that could literally change But they're not one-size-fits-all. We'll break down the differences, who they're best for and what to consider when deciding if either option is the right next step for your family. 

So, yeah. 


What is Food Immunotherapy?
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Dr. Kara Wada: Dr. Meagan, can you just share a little bit about like what is IT and food IT?

Dr. Meagan: Yeah, so immunotherapy in general, we'll just kind of start with that. And the goal with immunotherapy at its basis is that we're trying to teach the immune system to recognize things in a non-inflammatory way. And typically, it's something that your body recognizes as an allergen through repeated exposure or particular specific types of exposure, we can get your immune system to recognize that in a more safe, normal way. And there are different types that are done for environmental allergens. We also do it now for foods, which is the, of course, subject of what we're talking about today, but it's such a big deal because there's so much food allergy out there now.


OIT vs. SLIT: The Key Differences
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Dr. Meagan: So for a long time what we had talked about in the past with food immunotherapy was something that we call OIT and that stands for oral immunotherapy. And so that is referring to a type of immunotherapy where you are given the food in some type of form. And Dr. Patterson is gonna get into the nitty gritty of this, but you basically swallow it.

So it's a pretty simple process by words. In reality, it requires a lot more, a lot more detail. For SLIT, that stands for sublingual immunotherapy or SLIT. And so that is where you put drops under the tongue. We have immune cells there that can absorb that and take those antigens into the immune system where it tries to teach your body to recognize it again in a non-inflammatory safe way.

So those are the differences between OIT and SLIT. And so I'm gonna turn the platform over to Dr. Patterson to talk more about it.

Dr. Amber: That was a great high level summary. Many people have heard of OIT since a couple years ago, there was the first FDA approved oral immunotherapy for peanut that came on the market. Many allergists under some common protocols that had been published, had been practicing OIT for a long time before that, for more than just peanut. But this was a big deal when that was FDA approved because it gave a standardized dosing, availability for maybe allergist who weren't doing OIT to finally have a way to offer this to their patients. So like Meagan said, the OIT is where you're ingesting actual food particles into your mouth, swallowing it, kind of like that normal eating process almost but starting with really, really small amounts.

I mean, we're talking not quite microscopic but almost, and at a level that even people with the most severe food allergy can usually tolerate and then gradually working way up. Whereas SLIT is the drops of the purified protein extract under the tongue that gets absorbed into the lymphatic system. And so it's two different approaches and I offer both in my practice and oftentimes parents who come interested in immunotherapy for food want to know, okay, well, which one, you know, we wanna do something. We don't just want to avoid the food. We wanna get to a better place with this food allergy. And they, they usually have two questions. They wanna know, which one do you recommend for my child, OIT or SLIT? And they wanna know what they can expect on the outcome of the treatment. And so first step is I like to flip the conversation and say, well, you tell me what you wanna get out of this.


What's Your Goal? "Bite Safety" vs. Full Reintroduction
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Dr. Amber: Because some patients, like classic example, teenager who has been told their whole life that they could die if they ingest a certain food even if all their testing is telling us that that sensitization has decreased to a point where they could try the food even like outside of immunotherapy, talking about an oral challenge. A lot of times they'll say, no, I don't like it.

I don't like the smell. I don't ever wanna try it. So that may be somebody who maybe they had some accidental ingestions, landed in the ER a few times, and now we're talking about immunotherapy for bite safety. So to get them to a place where if they accidentally eat something, they're not gonna end up in the hospital like they've been. So bite safety is one goal that some patients have. Other patients want to completely reintroduce the food into their diet. They may say, you know, I have always wanted to try a peanut butter and jelly sandwich. I want to be able to pack that in my lunch. So I try to get really specific on what their end goal is. And that can change.

And it can be different between the child and the parent too. If the patient is a child, sometimes it's the parent really pushing because they want that freedom for their child, but maybe the child doesn't, or vice versa. So anyways, step one is figure out what the patient actually wants because that can help guide your decision. And then for deciding which one to choose, there's also a few factors that go into that. So there's what is your history? What do your tests show? I usually get skin testing and blood testing. Have, you know, both things to compare. Different allergists do it different ways. Some will just use one or the other. Some will use component testing with lab testing. But basically taking the history, the blood, testing, the skin testing, the patient's goals. That's how we make a decision, do we proceed with OIT or SLIT? And in general, just kind of high level, hypothetically speaking, I would say that OIT tends to be great for people who want a more aggressive approach. It's a little bit stronger, might get you to where you want to be faster, but there's also higher risk of reaction with that. The SLIT, lower risk of reaction, little more gentle approach, may take a little bit longer to get us where we're going, but both have been successful. 


OIT: The "Aggressive" Approach (Higher Risk, Potentially Faster)
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Dr. Amber: And again, these are non FDA approved off-label treatments we're talking about except for the one peanut OIT.


SLIT: The "Gentle" Approach (Lower Risk, Slower Pace)
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Dr. Amber: But both have been successful in getting patients clinically to where they want to be in terms of being able to be around a food. Be bite safe with the food and or reach what we call sustained non-responsiveness, where you basically outgrow the allergy and can add it into your diet. 

Dr. Kara Wada: I wonder what your experience has been kind of with. I, I think one of the fears that I've had in regards to offering OIT in particular, one, just knowing I'm a brand new practice, I need some infrastructure to help support these patients, and their families. 

Dr. Amber: Yeah. 

Dr. Kara Wada: And, and, and helping them feel safe, you know, as safe as we can, you know, with something that inherently has some risk. Are you hearing and seeing like a lot of side effects, like tummy aches and, you know, those sorts of things that it, that we hear about or read about in, in the, in the papers?

Dr. Amber: Mm-hmm. Yeah. With OIT, it is, you know, the common side effects are, Typically GI, you know, upset tummy, sometimes some mouth symptoms. And so those are things if patients are experiencing those, that we've already given them some guidance on ways that they can manage that. But you know, if they've done an up dose and those symptoms are being persistent, not resolving with treatment, then we have to take a step back, maybe adjust down their dose.

Do a little bit longer at a lower dose and then move up. You know, just like with other forms of immunotherapy that we do, sometimes there's a little bit of adjustment along the way to getting someone to tolerate their immunotherapy, and so it's a really personalized approach. 

Dr. Kara Wada: Awesome. 

Dr. Amber: I think one other thing too, just to mention differences between the two that can impact your decision a little bit because it has to do with how many visits are required to get going. So OIT, there's usually an escalation day initially where you're in the office for hours starting with that little dose working.

Have you guys had patients that asked about these therapies? Do you feel like it's something parents are wanting? 

Dr. Kara Wada: Yeah, I think it's been on my radar as something I would love for the Immune Confident Institute to grow into. You know, part of, part of my issue one, I, we just started like a few months ago. and so need, needs some, some help, in getting, you know, getting the bandwidth to offer a treatment like that.

But we also will need a space to see patients because, primarily, while we're recording this, things are are more telehealth based than anything. So having that physical space to be able to do these up dosing visits and in, in sessions, I think will be critical as I, as I think about the growth and expansion of, of what we're able to offer our patients.

I wonder too, I know we've always, and this is, this is going out on a little bit of a limb and me just kind of hypothesizing, but for my patients with mast cell disorders, I do wonder many of them have symptoms that sure as heck look and sound and act and feel like true allergic reactions to foods. Their skin prick testing is negative or their serum IgE testing is negative. And so I asked this question more just to ask it, not that I'm planning on doing anything about it at this moment, but is there potentially a role for very small increased dose, you know, to try to desensitize the mast cells to whatever there it is they're reacting to. I don't know, but there are some other things that we, we do that for. 

A lot of the patients that I see there tends to be a latex, food, you know? so there are certain foods, mostly plant-based foods that all share protein structures that are somewhat similar, and so sometimes the immune system can get a little confused and mistake.

Birch tree pollen for apple, protein for almond protein. and for instance, with apple, if you peel and cook the apple, oftentimes it's no longer an issue. but the, those more, those proteins that show up time and time again, those oftentimes are ones that you can kind of connect some of the foods these patients are reacting to back to some of those elements. And so it does kind of give me this question of like, hmm, is there a way to work around that? 

I think that's what we have here on, you know, the beginnings of food allergy treatment. I am sure that this conversation is just going to spark additional questions, thoughts, concerns. Is this allergy actually? We wanna hear all of it in the comments. Make sure to like, make sure to ring the bell to follow us. You know, we don't have that spiel down. But we do wanna get this message out. And certainly if you are, you know, interested in connecting with allergists who are on the front line, who are really active and engaged in innovation and really taking great care of patients, make sure to check out the Auni® ILIT™ Learning Network and connect with someone who is engaged in your local area.

Until next time, this is 

Kara: Allergy, Actually.

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