What is Sublingual Immunotherapy, and How does it Work

Allergies are annoying at best and enough to make you absolutely miserable at worst. While there are treatments out there, like corticosteroids or antihistamines, that can offer relief, their effects are temporary. That’s where allergy immunotherapy, including sublingual immunotherapy, comes in.

This treatment is a promising solution to irritating allergies, allowing you to find long-term relief by repeatedly exposing your immune system to the allergen. In this article, we’ll discuss sublingual immunotherapy and how it works to help you decide if it’s the right fit for your needs. 

Understanding Sublingual Immunotherapy

Sublingual immunotherapy (SLIT) is one of two types of allergy immunotherapy. It’s administered under the tongue in the form of drops or tablets. The drops or tablets contain a small dose of the allergen, allowing it to work toward achieving an allergen-specific tolerance.

Since the chances of an adverse reaction are low, you can administer each dose from the comfort of your own home. Simply administer the number of drops under your tongue as instructed by your doctor, and let the drops work their magic.

At the time of writing, the FDA has only approved a select list of allergens sublingual immunotherapy can treat. However, researchers are looking to expand this list and add more common allergies to the mix.

How Does Sublingual Immunotherapy Work?

Sublingual immunotherapy works just like the other types of allergy immunotherapy. However, before we explore the workings of sublingual immunotherapy, it’s important to understand the basics of an allergy. Simply put, an allergy is your immune system’s reaction to a particular substance.

Your body produces antibodies, blood proteins that counteract a specific antigen, which may flag a substance as harmful, even if it isn’t. So, when your body is exposed to an allergen, those antibodies send out a warning, communicating with cells that release specific chemicals. That chemical release triggers an immune response, resulting in the allergies you recognize as an allergic reaction.

Sublingual immunotherapy works to combat that reaction by stopping it before it occurs. It focuses on the allergy, slowly “training” your body to become less sensitive. It does this by reducing the production of the “blocking” antibodies that kickstart the reaction, giving your immune system the chance to build an allergen-specific tolerance.

Over time and with consistent doses, sublingual immunotherapy can make a world of difference in your allergies. Of course, everyone is different, so results may vary. Most people begin to notice improvements within the first year, but it can take two to three years for the best results to show up.

Sublingual Immunotherapy vs. Other Types of Allergy Immunotherapy

Sublingual immunotherapy isn’t the only type of allergy immunotherapy. The second, called subcutaneous immunotherapy (SCIT), is administered under the skin via a needle. Like SLIT, this type of immunotherapy slowly desensitizes the body to a particular allergen.

However, since it has a higher risk of an adverse reaction, you’ll need to visit your doctor’s or allergist’s office for each injection. They’ll complete the injections and keep you at the office for a set period to monitor for an allergic reaction.

Additionally, since SCIT involves needles, it’s less popular for children. It’s widely used among adults, but it’s not usually the go-to pick for kids.

Is Sublingual Immunotherapy Effective?

Allergy immunotherapy, including sublingual immunotherapy, has been proven to be highly effective in treating various allergies. The treatment is nothing new, having been introduced over a century ago by Leonard Noon and John Freeman.

Since then, researchers have meticulously examined all aspects of its workings, uncovering its impressive efficacy. For example, one study evaluated allergy immunotherapy as a whole, focusing on its impact on allergic rhinitis. It found that both types of allergy immunotherapy offer clinical benefits and immunological changes that indicate an allergen-specific tolerance.

Another study compared an AIT-treated group to a control group. It found that the former was significantly more likely to step down asthma treatment and had substantial reductions in asthma prescriptions and allergic rhinitis compared to the control group.

These are just a couple of the many research articles and trials out there. You can find all sorts of research, some on specific types of immunotherapy or focusing on particular allergens. If you want to learn more about allergy immunotherapy, check reputable online sites (like the NIH) or your local library.

Closing Thoughts

Sublingual immunotherapy is a promising solution for irritating allergies. It employs tiny doses of whatever substance you’re allergic to, slowly desensitizing your immune system to it. With time and consistency, sublingual immunotherapy can dramatically improve allergies, allowing you to enjoy places and experiences you previously couldn’t.

Remember to chat with your healthcare provider before beginning any allergy immunotherapy treatment. They can help you determine the best type of allergy immunotherapy for your needs based on your medical history.