What is Sublingual Immunotherapy (SLIT)?

SLIT is an alternative method of allergen desensitization in the management of atopic conditions such as asthma and allergic rhinitis, which does not involve a series of injections.  The protocol for SLIT involves an allergist determining a patient’s sensitizing allergens, typically by skin testing, followed by small doses of these allergens placed under the tongue daily in the form of tablets or drops.  This causes a decrease in the body’s natural production of specific allergic antibody, called IgE.

Though SLIT is widely accepted and standard in Europe, not all SLIT therapy is approved in the US by the Food and Drug Administration (FDA).  A tablet form of SLIT for patients with grass and ragweed allergy (GRASTEK, ORALAIR, RAGWITEK) has been FDA approved and is currently available for physicians to prescribe.  While yet to be approved by the FDA, sublingual drop therapy formulated by your Allergy Partners physician is available for “off label” use.

Does it Work?

There is mounting evidence that SLIT is an effective treatment strategy in the management of allergic conditions.  A recent systematic review in the Journal of the American Medical Association states: “The overall evidence provides a moderate grade level of evidence to support the effectiveness of sublingual immunotherapy for the treatment of allergic rhinitis and asthma, but high-quality studies are still needed to answer questions regarding optimal dosing strategies.”1 Though evidence supports SLIT being more efficacious compared to some traditional treatment strategies, it is very clear that subcutaneous injection immunotherapy (allergy shots) is favorable to SLIT in reducing allergy symptoms.

What Are the Side Effects?

In general, SLIT is well tolerated.  Patients may have oral itching or mild tongue swelling after the first 3-4 doses.  However, these symptoms typically subside.   Other potential side effects include:  trouble breathing, throat tightness, throat swelling, dizziness, rapid heartbeat, severe stomach cramps, vomiting, diarrhea, and severe flushing of the skin.  As there is risk for anaphylaxis, all patients on SLIT therapy should have access to an epinephrine pen and be trained on its use and the first dose of SLIT is administered in a physician’s office.

Is it For Me?

There are certainly advantages to SLIT.  Published data does demonstrate clinical efficacy and you can expect to see improvement in your allergy symptoms.  For patients with busy schedules, SLIT makes immunotherapy less cumbersome as treatment can be given at home.  For children with “needle phobia,” SLIT provides an alternative option to avoid weekly injections.  Although allergy shots are the most efficacious form of immunotherapy, there undoubtedly is a role for SLIT in the management of allergic disease.  Talk to your Allergy Partners physician about whether SLIT is the best option for management of your allergy symptoms.

Reference

Sublingual immunotherapy for the treatment of allergic rhinoconjunctivitis and asthma: a systematic review. JAMA. 2013 Mar 27;309(12):1278-88.