The “short answer” is that your initial course of SLIT at Allergenuity Health will typically be designed for 4-5 years, including a build-up phase of 1-3 years and an initial maintenance phase of 1-2 years. That being said, there is significant variation from this due to many factors, and it is very important to have the correct understanding and expectations regarding what immunotherapy (of any kind) can do for you and how long you may benefit from treatment. If you’re interested in more information to better understand this topic, see the “long answer” below.
During SLIT treatment: The immune system is known to act based on a combination of signals from your genetic factors and your environmental exposures. Since we do not have control over genetic factors, we cannot change those fundamental signals your immune system is receiving. However, we can work together to provide as many tolerance-promoting environmental signals as we can, thereby training or retraining your immune system by educating it to look at its environment (including foods) more tolerantly. Most people begin to feel better and notice some protection from exposures when their immune system picks up on these non-threatening, controlled environmental signals. This is the allergy control and symptom relief you experience during the initial months to years on your SLIT treatment, for environmental or food allergens alike.
It can be tempting to stop your SLIT treatment earlier than recommended when you are feeling significant symptom relief, but the reason it is not recommended is that this usually leads to symptoms recurring fairly quickly once you have stopped since they were under control due to the allergen exposures and active signals coming from your SLIT treatment. Both the science behind immunotherapy and the clinical and research data collected over the past century strongly suggest that if your goal is to maximize your tolerance-building and potential for developing some sustained tolerance off of your treatment, you should remain on your treatment through your entire buildup phase and a 1-2 year maintenance phase.
After SLIT treatment: The longer your immune system continues to receive these favorable signals from your SLIT treatment, the more of a chance it has (and the more time it has) to actually break down the infrastructure needed to cause allergy symptoms and allergic reactions. This requires changes in more than just the amount of IgE produced, including changes in the numbers of certain cells in your body, the numbers of certain receptors on your allergy cells, and your immune system’s decision-making process when an allergen is encountered. For some people, if enough of this infrastructure is broken down and your genetic and environmental factors are also now cooperating with one another, a period of time off of SLIT treatment in which allergen tolerance persists can be possible. It is important to remember that this “sustained tolerance” time off of immunotherapy is not a guarantee for anyone on any form of immunotherapy (allergy shots, SLIT, OIT, etc), and it is not a cure. The way to have the most consistent symptom relief and allergen protection, as we currently know it, would be to continue on immunotherapy in order to always benefit from the controlled allergen exposures and active tolerance-promoting signals it provides.
Studies suggest that for environmental allergy-related conditions, the period of sustained tolerance off of either allergy shots or SLIT treatment is often at least 1-2 years. In our long-term SLIT experience, this can last much longer for some people. Similar studies for food allergies are lacking, but preliminary information, especially on rush or short-term food desensitization immunotherapy, has not commonly seen sustained tolerance after any form of immunotherapy treatment (OIT, SLIT, etc.) In our experience, however, periods of sustained tolerance for many food allergy-related conditions has been achievable for several individuals and appears to be more achievable the longer and more dedicated the course of SLIT up front.
What to expect: From over a century of trials, studies, and observation of patients on various forms of immunotherapy, it appears that at least 3-5 years committed to immune-training (signaling) treatment is important to have a decent chance at your immune system choosing to create more permanent tolerogenic changes during the process. These types of changes provide a form of long-term lasting effect (a period of sustained tolerance) without also needing the signaling method (immunotherapy) as well. Some data suggests that 4-5+ years on SLIT can be more beneficial than 3 or less years, with a longer up front time on SLIT leading to a longer period of sustained tolerance afterward. Some people may repeat another course of SLIT if their sustained tolerance begins to wane at some point, and there is good data that suggests a subsequent course can improve your symptoms and help you regain control of your allergies more quickly than the first. For some, perpetual SLIT treatment without time off may offer them the most protection and/or symptom relief, and this option can be a great and more natural long-term management strategy when compared to the other options such as chronic medication use to suppress symptoms or keeping up strict avoidance measures indefinitely.
Using all of these properties as we currently know them, your initial course of SLIT at Allergenuity Health will typically be designed for 4-5 years, including a build-up phase of 1-3 years and an initial maintenance phase of 1-2 years. Those with less allergens, less severe allergies, less risk factors, less chronic illness, or who have been on some form of immunotherapy before may be able to see benefit from a higher starting dose, a quicker buildup, and/or a shorter maintenance phase. Those with more complex issues may require a more gradual start, a slower buildup, and a longer maintenance phase to tolerate and benefit from the treatment. Dr. Schroeder will evaluate your individual factors and your goals and then design a sublingual immunotherapy treatment plan specifically for you. She will actively manage and adjust your treatment course while you are on it should circumstances change or your symptom control and test results suggest adjustments should be made in either direction. Therefore, your course on immunotherapy could be shorter or longer than someone else you know, or it could change at some point after you start, but you will always be informed about why it is what it is and will have direct input and communication with your allergist on the entire process.
How this works with our Programs: If you are on one of Allergenuity Health’s Programs, your Program length will cover your buildup period and at least the first year of your maintenance period. At some point after that, if you are doing well (which you hopefully are!) and are not requiring as many medical services and as much active management of your SLIT treatment as previously, we will discuss with you how to transition to your next phase – whether that is doing a trial off sublingual immunotherapy to assess for sustained tolerance, or it is remaining on SLIT for some time but switching to a Graduate Program or the Fees For Services system. All of these options will reduce your expenses while maintaining any immunotherapy or medical services with us that you specifically need or desire.