Allergy immunotherapy works by altering the abnormal immune response that causes allergy symptoms. Immunotherapy is the only clinically proven method of treating the underlying cause of the body's allergic response, and not just the symptoms.
Sublingual immunotherapy (SLIT) is a more patient-friendly form of immunotherapy (compared to allergy shots).
Instead of subcutaneous injections (allergy shots), SLIT involves sublingual (under-the-tongue) drops / sprays. A 2014 study found that "SLIT represents a safe and effective strategy to help with management of allergic diseases in both people and animals."
SLIT can either be customized for each dog, based on results from a skin or blood test such as ELISA. Or the shots can be standardized, as in RESPIT (Regionally-specific Immunotherapy). In RESPIT, the dog does not need to undergo allergy tests, and the allergens included in the shots are selected on the basis of what pollens occur in your region, the seasonality of your pet’s signs, and what other pets have responded to in the past. Studies have found that RESPIT is as effective as customized immunotherapy shots or spray formulations.
ALLERCEPT® Therapy Drops are sublingual drops which are approved for treating allergies in dogs and cats.