An Inside Look at Sublingual Immunotherapy

Sub-Lingual Immunotherapy has so many benefits that go unmentioned in today’s allergy conversation. It would be great to bring better education on the topic.

Allergenuity Health SLIT brochureSeveral years ago, Dr. Paul Ehrlich explained why he wouldn’t be taking up any of the new food allergy treatments that were coming into the medical marketplace. He wasn’t against it in principle so much as he wasn’t prepared to offer the kind of attention required when therapy consists of daily doses of the offending foods. He described such a practice in this way: If you are going to use this kind of therapy, the kind of practice you should go to, [is] one where current practitioners are either pioneers or who have worked directly with the pioneers.” We found one. Nikhila Deo Schroeder, M.D., who also holds a Masters in Engineering from MIT, started her own practice in Charlotte, North Carolina called Allergenuity Health whose aim is to safely teach and retrain the immune systems of allergic patients via a method called Sublingual Immunotherapy (SLIT) – the system of placing antigen under the tongue (via liquid or “drops”). After her Allergy & Immunology fellowship training at the University of Virginia, Dr. Schroeder worked for several years at Allergy Associates of La Crosse with Dr. Mary Morris, the standard bearer for the work done by her father Dr. David Morris, who attended a Sublingual Immunotherapy conference in the 1960’s and recognized the significant potential for this type of treatment in his mold allergic patients. Dr. Schroeder’s experience in La Crosse treating over 1000 patients with food and/or environmental allergies using Sublingual Immunotherapy gave her an in-depth look at how the immune system responds to this type of allergen introduction and ideas for its further therapeutic potential. – Henry Ehrlich

AAC: Thank you, Dr. Schroeder, for taking time with our readers. First I’m intrigued by your background in engineering. What made you leave for medicine?

Nikhila: Thank you so much for the invitation to talk with you and your readers, Henry! I’m so happy to be here. I have always had a love for math, logic, and problem-solving. Paired with my creative side, engineering was a very appealing career choice because it allowed me to use my skills to invent solutions for people. But being a doctor felt even more natural. My mom often shares the memory that when I was a really young girl, anytime someone was sick on our block, I would take them a can of chicken noodle soup from our pantry and keep them company. That’s just who I was and what I wanted to do from a young age onward. So in the end, I decided to go for both engineering and medicine and see what I could do with them together.

AAC: Does engineering inform the way you think about your allergy practice and your approach to patients?

Nikhila: Absolutely. My time studying engineering really cultivated my critical thinking skills and I apply that to my practice and my care of patients. Nearly every homework assignment or project at MIT was a complex problem that needed to be solved, and memorization or looking something up in our textbooks or on the internet was not going to cut it. Believe me, my friends and I tried. Though sometimes it was overwhelming, I’m so glad I pursued engineering first because it really taught me how to actively think and more importantly, to not be scared of doing so. Problems often have more than one solution, and that is a beautiful and extremely useful concept to remember in health. One solution may be the best overall for one person and a different solution may be best overall for another person with the same underlying issue. Being able to navigate, think, create, and adjust solutions to the individual person can help patients in ways that following a predetermined or standard solution simply can’t, so I’ve kept that idea central to my practice of medicine. Now that my husband and I have opened our own allergy clinic, we have incorporated these philosophies into not only our medical care but also into our overall health care process. Our clinic, Allergenuity Health, is in almost no way standard, and our approaches to everything from the care we provide to our business policies and price transparency are all designed to provide options and solutions to patients. It takes a lot of work, but it is worth it.

AAC: When you were doing your allergy training, was there much discussion of OIT and SLIT? What prompted you to pursue SLIT over OIT?

Nikhila: OIT and SLIT were essentially theoretical treatment possibilities during my fellowship training. They were an occasional topic of a research presentation or a Journal Club discussion. This makes sense to a large extent, since fellowship programs are designed to train budding allergists in the main diagnosis and treatment methods of the field, not necessarily in highly sub-specialized areas of the field. However, when I saw how much allergy patients and families were suffering and how inadequate the traditional therapies were in so many instances, I was motivated to look for or create something better and to further sub-specialize. I became very interested in immunologic signaling and how we could use that to help people with allergies. As I learned more about various types of immunotherapy, SLIT made a lot of sense to me. It actually made more sense overall than any other form of immunotherapy. It is scientific, uses a natural route of tolerance-training literally handed to us by our bodies, has been proven effective, and is safer than any other form of immunotherapy. Why weren’t we talking more about this? I still don’t know.

The safety aspect was the kicker for me that solidified my in-depth pursuit of SLIT. I had listened intently as so many patients and families shared their incredible stories, their worries, and their goals with me over the years. Safety, both in daily life and in treatment options, was overwhelmingly their main goal. What they desired most (other than a complete cure of course) was a treatment option that provided them with a safe way to build allergen protection, reduce chronic symptoms, and minimize the likelihood of anaphylaxis if they accidentally encountered their allergen(s). For example peanut-allergic patients and families made it more than clear that being able to eat peanut butter was not their goal, especially if they had to undergo a risky procedure to get to that point and then sustain a lifelong, daily risk to maintain it. And I completely saw their point. OIT’s risk of anaphylaxis for patients was and is still far too great for most specific patient situations, in my opinion. Some reports suggest that the average risk of anaphylaxis from OIT treatment may even be higher than the average natural risk of anaphylaxis in a food allergic patient. Though epinephrine is a life-saving medicine in anaphylaxis, it is not effective to rescue 100% of individuals from anaphylactic reactions even when used early and appropriately, so I take risk of anaphylaxis from a treatment extremely seriously. Given that SLIT can achieve many very useful and potentially life-saving results in a very safe way, without this substantial risk of anaphylaxis from the treatment itself, I knew that I personally would not be satisfied without seeing first-hand what SLIT could offer all of these patients looking for such an option.

SLIT bottles and teal pumpkinAAC: So what did you find that Sublingual Immunotherapy (SLIT) could offer patients?

Nikhila: Essentially everything patients desire. SLIT checks off nearly all the boxes of an ideal allergen immunotherapy treatment.

  • It is non-invasive. No shots, no pain.
  • It can be used to treat environmental allergens and food allergens, and more than one allergen at once if needed.
  • It can be used even in severely allergic patients.
  • It is easy for patients and families to do.
  • It is high reward for low risk, helping patients build substantial levels of protection without a significant risk of anaphylaxis from the treatment method itself.
  • Its most common side effect is a temporarily itchy mouth.
  • It can be done at any age, including as early as infancy.
  • Depending on the method of SLIT, it does not require any significant exercise limitations, rest periods, or lifestyle restrictions. And missing an occasional dose when “life happens”, even during the buildup phase has no detrimental effects on the overall level of protection you have developed.
  • It is non-intrusive. There is no need to find ways to get your child to eat something they may not like the taste of or that is anxiety-provoking.
  • It saves families a lot of time and money in the long run – much less ER and other doctors’ visits, less testing, less medications.
  • It can be done with infrequent appointments – nowhere near weekly or monthly like other forms of immunotherapy.
  • It can dramatically improve a patient’s (and their family’s) quality of life with significant symptom relief and substantial allergen protection over time.
  • Some patients can come off the treatment and have sustained results for some time. For those who have better relief and protection on the treatment than off or for whom it may be too risky to gamble with discontinuing, it is extremely easy to continue long-term.
  • It is easy to travel with when needed, and treatment can be done and maintained long-distance if you’re on a trip, away at college, or move to a different state during the course of your treatment.
  • It involves forming a simple habit just like brushing your teeth, but even easier.

Liquid antigen SLIT treatment is done by literally just holding a sweet-tasting liquid droplet – a very specially formulated one – in your mouth a few times each day. Like any form of allergen immunotherapy, achieving substantial, true immunologic change does take time and a commitment. But I have not currently come across anything better than SLIT to help most patients and families safely build towards their goals and improve their quality of life.

AAC: Is there anything that SLIT doesn’t offer patients that OIT does?

Nikhila: Yes, there is one main limitation of food SLIT compared to OIT. SLIT will not be able to give a patient or family real-time information on their exact level of developed tolerance or desensitization. For patients on food SLIT, the allergen amount a patient can tolerate if ingested is typically much higher than the SLIT dose being administered, but we don’t have an easy way to know exactly what that amount is at any given time point in the process (without doing an oral challenge) since the treatment does not involve someone actually ingesting the food as OIT does. With OIT, since you are ingesting a particular dose of an allergen each day, you know that if the next day you were accidentally to ingest up to that same amount of the allergen before you took your daily dose, you would probably be ok (unless you were exercising, hot, stressed, or ill at the time, so it is still not a guarantee). Though I wish this limitation didn’t exist, SLIT is not alone in this. It’s similar to allergy shots in which we cannot answer this question in real-time either. However, in the case of allergy shots and environmental SLIT, patients are naturally and repeatedly exposed to many of their environmental allergens, so they physically see their results at those times since those are essentially allergen challenges. With food SLIT, since you’re also avoiding the food at the time (at least initially), we can’t really use that method either unless you have an accidental exposure.

Here is what we do know though, which helps support patients through this limitation with SLIT:

  • Studies that have challenged patients after even short SLIT courses have demonstrated substantial protection, with improvements in tolerance from their pre-treatment level of over 100-fold. The longer the time on SLIT treatment, the further this increases.
  • Short-term studies have shown that successfully consumed doses in challenges have ranged from 250-2,500 or more times the SLIT treatment dose at the time. So we can make some educated estimates. (And again, the longer the time on SLIT treatment, the further this can increase.)
  • Anecdotal experience with accidental exposures repeatedly shows significant protection gained already within the first year and even more in the subsequent years, and we get more than enough evidence of the power of SLIT to protect against allergen exposures from what we see with environmental allergy symptom relief to frequent natural allergen challenges.
  • There are clues of the protective immunologic changes that we can see in test results as well (though we have a long way to go as a field in terms of getting access to much needed better tests in this area).

AAC: SLIT and OIT are often compared as if they approach “desensitization” via the same mechanisms. Is that true?

Nikhila: SLIT and OIT can be used similarly or very differently. That’s where a lot of confusion comes from, even by physicians. Not all procedures offered under the same name do the same thing. And one version of SLIT is certainly not the same as another version of SLIT, so it is important that patients research and interview providing physicians. The underlying knowledge of immunologic mechanisms, immunotherapy design skill, type of protocol, and experience of the providing physician can make a huge difference. This is probably similar to OIT since both SLIT and OIT are sub-specialized treatments. I’d be happy to help explain the basics of these comparisons here.

AAC: So how can SLIT and OIT be used similarly to achieve desensitization?

Nikhila: Classic desensitization by OIT or SLIT is similar to what we offer in the hospital to desensitize penicillin-allergic patients if they really need penicillin treatment for a particular infection. The process involves introducing a particular allergen into the body in a fairly quick, increasing, step-wise manner. This essentially plays a trick on the immune system, which is why results are so quick and can be so high. But along with this type of result comes significant risk. There are two main parts to how this type of desensitization trick is achieved, which would take quite a bit of time to explain fully. But the basics of it are, one of the things that introducing allergen in small, increasing, repetitive ways can do is use up the system’s allergic mediators bit by bit by activating allergy cells in chunks until all the mediators have been released. This is of course not without risk of the patient developing some type of symptom along the way, and symptoms do commonly occur in classic desensitization procedures as allergy cells are activated. The hope is to stay under the threshold of anaphylaxis, but that unfortunately is not always the case because there is no way to know what that threshold is. The other thing that increasing, repetitive introduction of allergen can do is slowly flood the system with so much allergen that it gets a chance to bind in many more places than usual, including plugging up both binding sites on IgE antibodies, effectively blocking IgE antibodies from cross-linking with each other which is a main signal needed for activating allergy cells. So, both of these types of actions can occur as a person gets desensitized, rendering their allergy mediators either all used up or their IgE antibodies all blocked up or striking some sort of balance in between. Regardless of exactly what occurs, once the short-term desensitization trick is achieved, the immune system is in a balanced state of “temporary tolerance” in which it still very much wants to react when it sees that allergen – it does not think the allergen is any less harmful than it did before – but it is just much more difficult for it to be able to do so. In order to keep the body in this type of desensitized state, a persistent and high amount of that allergen needs to remain in the system, at least for quite a long time if not indefinitely. It has been well-proven that in the short term, if the high allergen load is stopped, the patient’s immune system has a very good chance to replenish its allergic mediators to substantial amounts, and all the allergen plugging up the IgE antibodies gets a chance to be released such that these IgE antibodies can cross-link again. And when those things happen, allergic reactions to allergen exposures can again occur. For patients receiving drug desensitization to penicillin in the hospital, once the procedure is stopped, we make it a point to emphasize to them that they are still very allergic to penicillin and they should not take it again on their own for anything else even though they just took it for treatment at high doses.

Classic desensitization is an incredibly cool trick, but it is kind of like cheating on a test. The immune system appears to know how to handle an allergen, but in the short run it didn’t actually learn much about how to properly handle that allergen, and that can come back to haunt it. That’s not to say this type of desensitization is not without its uses, or that there aren’t potentially additional beneficial long-term effects if desensitization is carefully maintained (but our understanding of this is in its infancy since we do not maintain drug desensitization long term). What is very important is to understand this type of desensitization for what it is – a quick, high-dose, temporary fix that comes with risk, is high maintenance, and can fairly easily come undone. Since the main component of this desensitization is merely being able to get an allergen into the system repeatedly and at higher and higher doses, either OIT or SLIT can be used effectively for this purpose. OIT can more easily reach higher doses because you are using the actual food so you can consume as high of a dose as a person needs to institute this trick, but that comes with the disadvantages for some people in terms of not liking the taste of the food, as well as the risks of allergen ingestion and entrapment in the stomach. If a reaction begins after an OIT dose, it is not easy to remove the allergen from the body and minimize the reaction. SLIT can also reach substantially high doses because you need much less allergen (1000 times less or possibly even less) presented via the sublingual route to achieve similar results to the gastric route, but there are some limits to how much allergen can be physically held in the sublingual space as well as the expense of FDA-regulated, purified liquid antigens. However, if a reaction begins to occur with a SLIT dose, the antigen can be spit out and the mouth can be rinsed out to try to disrupt any further allergen capture, so risks and reactions can be better managed. The takeaway here is that substantial desensitization of this type can and has been achieved with both SLIT and OIT methods. OIT can reach higher doses (if needed) more easily, but the safety with the SLIT route is overall better and the taste factor is a non-issue with SLIT since the allergen is in a purified liquid form.

AAC: And how can SLIT be used differently than OIT and other forms of immunotherapy?

Nikhila: This is the crux of why I personally find SLIT to be superior as an overall immunotherapy option and as the best place for most patients to at least start if not also finish. Sublingual Immunotherapy (SLIT) has the unique ability of exposing the immune system to its allergens via special highly tolerogenic (tolerance-promoting) immune messenger cells found only in the mouth. These cells are called oral Langerhans cells, and they are very efficient at capturing substances present in the mouth and then sending calming signals to the rest of the immune system via specific tolerance-promoting natural chemicals (cytokines such as IL-10 and TGF-b) and important T and B cell influences. In fact, this appears to be the main part of their job – to help the immune system learn to tolerate the exposures seen regularly and non-threateningly in the mouth. This has been supported in basic science studies, but it makes common sense too. Our vital substances all come through the mouth – water, food, air – and we need to overall be able to tolerate them in order to survive. These cells help teach the rest of our immune system what to tolerate. We can use them to help teach our immune system that “allergens” are harmless too.

Though the sublingual route can be used to attempt to achieve the classic type of desensitization I described before, it can also be used in a different way to try to retrain the immune system to think properly about allergens. This form of SLIT often includes many of a person’s allergens (not just one) and uses a lower and slower approach to allergen introduction. By purposefully giving low doses of the allergen, especially at first, the allergen is mostly picked up by the special tolerogenic messenger cells I mentioned before (oral Langerhans cells), engaging those tolerance promoting mediators. Very little of the allergen in the treatment reaches the mast cells (allergy cells) in the mouth or elsewhere in the body, so very few allergic mediators are released and therefore symptoms are minimal and risk of anaphylaxis is essentially only theoretical when SLIT is done this way. (For example, I have not seen anything close to anaphylaxis from the SLIT treatment I have done in over 1000 patients now.) This type of SLIT method allows a skilled allergist to very safely direct the immunologic signals being generated in favor of tolerance-promotion rather than allergic pathway activation, thereby retraining the system towards realizing that all of these substances it thinks are dangerous allergens are truly harmless at baseline, and that activating allergy pathways is not a productive response. It is akin to giving the immune system a tutor to help it understand a concept that it had gotten confused about before. In the short term, fostering these calming signals can reduce inflammation and decrease the reactive cytokines released via allergic pathways. This lessens both symptoms of chronic allergic disease and a person’s immediate reactivity to their allergens. In the long-term, creating a persistent environment of these calming signals causes many favorable effects: a shift in the entire immune system away from desiring to produce IgE and towards producing other antibodies, downregulation of IgE receptors so any IgE produced becomes less able to cause detrimental actions anyway, and a change in the overall composition of immune cells away from those involved in creating and perpetuating allergic pathways and towards those found in tolerant, non-allergic individuals.

I have seen such good things come from this type of SLIT approach without significant inconvenience to families or safety risk to patients. And that makes this type of SLIT treatment extremely valuable and unique compared to all other forms of immunotherapy.

AAC: SLIT has been criticized for a lower reported efficacy than OIT. Can you help our readers navigate this comparison?

Nikhila: Of course. The efficacy comparison has been so oversimplified so frequently that it has led to a lot of perpetuated misinformation and confusion. But this is understandable because these topics are so complex that quick summaries by default miss and skew crucial points. I won’t even be able to get into the half of it here either without going on for hours, so I’m happy to talk more about it with anyone interested. The main thing it is really important for patients and families to know is that both OIT and SLIT are effective options to choose from. Risks of reaction to exposures generally improve by substantial levels with either method. SLIT does not only max out at “bite-proof” for everyone, and this has been clearly proven in peanut SLIT studies with many participants being able to eat anywhere from 1-20 peanuts after a relatively short SLIT course. It has also been shown in a milk SLIT study with participants being able to tolerate 1/8th-1 full cup of milk. And I have seen a wide range of incredible results in private practice as well to further confirm the potential with SLIT. Think about it – to be able to safely improve a peanut-allergic patient’s tolerance to even just 1 peanut, let alone potentially much more. That is what the vast majority of patients in the real-world want, so why isn’t SLIT being promoted more as an available, sub-specialized option? It doesn’t make much sense that it is not, except that the definition of efficacy has unfortunately strayed from what many patients truly desire to what type of high-dose result can be academically achieved.

The commonly used marker of “efficacy” in discussion is “high-dose tolerance as quickly as possible.” If that is the entire definition of efficacy, with no regard to safety or other factors, then a classic desensitization procedure via either OIT or SLIT would be the best route, with an advantage to OIT since the dose can easily be increased however high is needed to achieve the desired result for an individual. However, if we take into account what is desired by a particular family in their real-life in terms of what level of protection is effective for them – balanced with other factors like the risks of achieving that protection in a certain time-frame and the required maintenance to keep it up indefinitely – then “efficacy” takes on a whole different definition. Most patients are not looking to be able to fully eat a previously anaphylactic food. Many don’t even like the taste. They just want to be able to live their life as “normally” as possible with as much protection from accidental exposures, as minimal interference in their life, and as low of a safety risk from the treatment itself as possible. For these people, SLIT is the most effective option. And even for those who do want to be able to eat full servings of a previously anaphylactic food someday, SLIT may get them there, so it still is a great option to consider starting with given its other several benefits. If needed, OIT can be done afterward with a more safe and smooth course thanks to the beneficial foundation laid by the initial SLIT course. So it’s also important to not think these treatments are mutually exclusive – the solution for a particular individual may involve both. In the end, the overall efficacy of all of these treatments actually comes down to a family’s personal factors, and the simple, isolated comparison of “tolerated dose in a short time-frame” can really mislead a family trying to understand all of their options.

The RTP SLIT Club 2018AAC: Who manufactures your drops at your clinic Allergenuity Health? Can they be combined to reduce the daily dosing burden or is each allergen treated separately? If so how many allergies can you treat simultaneously?

Nikhila: We formulate our own SLIT drops at Allergenuity Health, based off of my formulas and my direct, personalized management of the SLIT procedure course all along the way. We use FDA regulated antigens that come from the 3 major world-wide antigen companies who collect the allergen material and purify it into a liquid suspension. I absolutely treat multiple allergens at one time if possible for a patient, which greatly reduces patient burden and time to protection as well as has many other synergistic health benefits. We keep environmental and food allergens separate for logistic reasons, and in our typical dosage range I can fit up to 20 allergens in each bottle. That allows me to treat up to 20 environmental allergens and 20 food allergens with my most common method, and I have found that for most patients that is more than enough. Additional allergens or more concentrated high doses can be made available if needed, as I am always open to optimizing the treatment structure to each patient, so we get creative if need be to make a plan best suited to each patient.

AAC: Do you have any exclusion criteria for new patients such as uncontrolled asthma, EoE, or a history of frequent severe reactions?

Nikhila: This is a great question and the answer is – no! In fact, one of the wonderful features of the kind of SLIT I do is that I can actually use it to help all of these patients who are so often excluded from immunomodulatory treatments for safety reasons (which I’ve always found ironic since these are the patients who could benefit from immunotherapy the most). I use additional precautions in these patients to make sure that we really ease into allergen introduction to their body, but the beauty of this treatment method is that tolerance-generating mediators are released by the immune cells we are engaging with allergen, not allergic mediators. So, the allergen we’re introducing via the sublingual route is not significantly activating their allergic disease, but rather helping healing mediators be released. It’s pretty incredible that allergen particles can be both the problem and the solution, depending on the signal they send. But it makes sense because “allergens” are truly harmless themselves. SLIT has finally given me a fantastic and safe way to truly help all patients from mild to severe allergic disease so that no one is left out without an immunomodulatory option.

AAC: A few years ago we published an article about a Netherlands study that showed patient compliance with SLIT, which is better established in Europe than it is here, was lower than allergy shots. Last week I saw a presentation by a major figure in the field who showed similar data. She said the most important figure in getting good compliance is the doctor’s secretary who can call to remind patients. What is your experience with patient compliance? Also, she said that she doesn’t insist on SLIT patients carrying epinephrine. Where do you stand on that?

Nikhila: My experience with patient compliance with SLIT in private practice has been very good. I think that is because we make it a point to make sure that SLIT treatment is a good overall fit for the family before we start, and we make time up front to answer a family’s questions so that they understand how, when, and most importantly why they should properly take their doses. Additionally, we discuss what is and is not feasible for a family, and I take those factors as well as their medical situation into account as I formulate a personalized plan for them. As we go along, I tweak the plan as needed so that we can keep any symptoms from the allergen exposure in the treatment as minimal as possible. When the treatment is easy, families understand what they need to do and why, and the dosing doesn’t cause too many adverse effects, compliance is generally good. Families do have to take some responsibility for dosing properly on their own since the treatment is largely home-based unlike allergy shots, but most families we work with are motivated and we do our part as well to best set them up for success without too much inconvenience or stress. We certainly don’t have a secretary that calls and reminds patients to take their doses, and thankfully we have not found that to be needed at all. From what I have come across, compliance is lower when high doses are jumped into early on which leads to adverse effects and when proper education has not been allowed to take place. This often happens when treatments become standardized and patients are pushed through quickly. Thankfully, I have left that part of our health care system and am able to approach SLIT treatment in a completely different way for my patients.

My policy on epinephrine for SLIT patients is different for each patient. In an ideal world, I think every person, known to be allergic or not, should have epinephrine rescue readily accessible. Anyone can have a surprise allergic reaction at any time, not just those who have had one before. So I am always happy to prescribe it. For SLIT patients, for those who have epinephrine auto-injectors prescribed for their allergic conditions, I recommend that they bring them to their up-dose appointments. (They should anyway because they should have them with them all the time.) However, for those on SLIT with no history or testing suggestive of severe allergic reaction risk, we discuss risks and the need for epinephrine and weigh all the factors. I will happily prescribe it, but that is not always what works best for a patient. It is my job to educate them and help them make the best decision for them. Carrying epinephrine in its current form certainly affects many aspects of a person’s lifestyle and routine, and it can be very expensive. So prescribing it just for it to sit in a drawer or never be picked up is also not useful if the patient’s risk for anaphylaxis is extremely low and they are not concerned. Since the method of SLIT that I do is overall so safe and nothing close to anaphylaxis from proper dosing has ever been an issue, I agree that from what I’ve seen, mandatory epinephrine carrying for certain types of SLIT treatment does not appear to be warranted and it should be discussed on a case by case basis.

AAC: Your website is quite detailed and clearly tilted in the interests of patients, including the creation of community. How did you arrive at this approach?

Nikhila: It’s just what we want to do. My husband and I see a community and building strong relationships as the foundation of all good things in life, and we have both always been very service and community oriented. None of us do better alone than we do together with great and supportive people at our sides, and everyone’s health benefits from “TLC”. We were so tired of the often cold, competitive, and lonely nature of the standard, insurance-managed health care system in this country, both from the patient and physician perspectives. So when we decided to open our own clinic, we made sure to structure it based on our own values. Our patients become like family to us. We know our patients’ names, and their parents’ names if they are a child. We know about their favorite animal or toy if they’re a child or their hobby if they’re an adult. We give our young patients “superhero support” and “bottle buddies” to let them know that they are strong themselves but they are also not alone. We connect them to one another, and we have plans to do specific types of Allergenuity Health community events as we continue to grow. Knowing you are a part of a caring community can sometimes make all the difference, and we want our patients to never feel alone because once they’ve joined us, they never are.

AAC: Do you have any thoughts for your fellow allergists who are on the fence about offering new therapies or are firmly opposed?

Nikhila: My personal approach has always been simple – to make sure to keep an open mind about new or additional treatment possibilities that appear to make some scientific and common sense, and that has served me very well with my patients. But it has also not been easy to do so in this insurance-driven healthcare culture that so strongly restricts all of us to mass standardization and protocolization of healthcare and away from critical thinking, innovation, and personalization of care. So I completely understand why not all of my colleagues may embrace the same approach that I have. I guess I would encourage my colleagues to try hard to keep an open mind about reasonable therapies even if they are not interested in or willing to offer them and to not dismiss a therapy or procedure based on summarized data without first trying to gain a better understanding of it. Though there are as many if not more terrible, unfounded therapies being pushed out there as there are great, underutilized therapies, if one or more of our allergist colleagues really stands behind a treatment, I would hope it would at least beg the question from fellow colleagues of “I wonder why?” and a subsequent “Let me reach out to my colleague and find out more.” The more we are open to listening to and learning from one another about things we have not thought deeply about or experienced ourselves, the better we can learn from our collective experiences and come together to help allergy patients. We don’t need to all offer the same highly specialized treatments, and in fact that would probably not be feasible because there are reasons that these treatments are highly specialized. But if we learn which of our colleagues is skilled at which treatment, and if we make an effort to understand what each treatment can offer patients, we can guide our patients to the best options for them whether or not we offer them, and that is what we are all here to do as the experts in our field.

AAC: Do you have final any thoughts for patients pondering their treatment options?

Nikhila: Choosing a treatment option is a very personal decision and there is no right or wrong. No single type of treatment is going to be the right choice for everyone, and thankfully there are several effective options available for patients and families to choose from (though some may require travel, as we have only been open a couple months and are honored to already be working with patients from 11 different states). SLIT offers significant benefits to the majority of allergic patients in a safe, easy, and convenient way, which is why I have chosen to specialize in comprehensive SLIT treatments and help make them more available to patients. But I also completely respect all the other treatments available and discuss them with patients regularly, including the option of avoidance, as each option has specific merits that may be a better fit for certain families.

In that light, I’ll share some final guidance here for families that may be trying to choose between starting with SLIT or OIT (or SLIT or allergy shots). Since each of these treatments has been proven effective to a substantial degree, it often really just comes down to thinking about your top priority/goal/concern and which treatment suits that best to start with:

  • If you are concerned about a treatment’s risk of anaphylaxis, SLIT would be the better route for you.
  • If your primary priority is being able to eat an allergenic food in large amounts as quickly as possible, OIT would be the better route for you.
  • If you don’t like shots, SLIT would be the better route for you.
  • If you have multiple allergens or some type of chronic allergic condition (eczema, asthma, seasonal allergies, etc), multi-allergen SLIT would be more helpful for you overall. SLIT would be a good initial foundation to calm down your immune system in general first if you are planning to later pursue OIT for one allergen in specific.
  • If you need to know in real-time exactly what minimum amount of the allergen can likely be tolerated, OIT would be the better route for you.
  • If your allergic child is very young, SLIT would be the better (and possibly only) safe immunotherapy option for you at this time.
  • If your child doesn’t like the taste of the allergenic food, or if you cannot keep up with or don’t want to deal with the exercise, rest period, and other restrictions, SLIT would be the better option for you.

Thank you so much for the opportunity to speak with you and your readers.

AAC: For videos of Dr. Schroeder’s patients taking their medicine click here and here. Looks easy!

Nikhila Schroeder MD MEng - Allergenuity HealthDr. Nikhila Schroeder is board certified in both Allergy & Immunology (adult and pediatric) and Pediatrics. She was born and raised in Wisconsin. She attended college in Cambridge, Massachusetts at the Massachusetts Institute of Technology where she obtained both Bachelor’s (2004) and Master’s of Engineering (2005) degrees in electrical engineering and computer science with concentrations in biomedical engineering and music. She went on to medical school in Madison, Wisconsin and earned her Doctor of Medicine degree from the University of Wisconsin School of Medicine and Public Health in 2009. She then completed her Pediatrics Residency training program (2012) and Allergy/Immunology Fellowship training program (2014) both at the University of Virginia. From 2014-2017, she treated nearly 1000 patients with sublingual immunotherapy from all over the country. In 2018, Dr. Schroeder and her husband James Schroder decided to move their family to Charlotte, North Carolina and open Allergenuity Health Associates together in their vision, as a direct care comprehensive sublingual immunotherapy treatment center, to bring high-quality, scientific, comprehensive sublingual immunotherapy treatment regimens and a healthcare model that supports a strong patient-doctor relationship (including patients having direct access to their allergist) to the region. For more information go to

Patient photo by permission of families, granted to Allergenuity Health.

Article Published By

Ehrlich, Henry, and Nikhila Schroeder. “An Inside Look at Sub-Lingual Immunotherapy.” Asthma Allergies Children, Henry Ehrlich, 1 Nov. 2018,

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