Allergy immunotherapy shots work 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. Allergic immunotherapy treatment is usually considered when allergy symptoms are moderate to severe, occur throughout most the year, do not respond adequately to medications, and are triggered by allergens that are not easily avoided, such as pollens or house dust mites.
Allergy shots 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.