ABSTRACT
Subcutaneous allergy immunotherapy (AIT) may be considered for patients with allergic rhinitis and/or asthma who demonstrated specific IgE sensitization to allergen to which they are significantly exposed and whose pattern of occurrence corresponds to that of the patient's symptoms. The ability to control symptoms with pharmacotherapy does not preclude the addition of AIT since only the latter modifies the underlying immunologic derangement and provides protection against progression from rhinitis to asthma and persisting benefit for many years after a 3- to 5-year course of treatment. Important considerations in preparing a vaccine for AIT are that the maintenance dose should contain an adequate amount of each allergen. Vaccines containing multiple unrelated allergens are effective provided that the delivered dose of each allergen is adequate. Extracts of pollens, animal danders, and house dust mites should not be mixed with cockroach or fungal extracts as the latter contain potent proteolytic enzymes that will degrade other extracts. Drawbacks to subcutaneous AIT are the prolonged period of buildup to the maintenance dose, the need to continue maintenance injections for at least 3 years, and the hazard of systemic reactions that mandate that injections be given in a medical facility, but for properly selected patients the results are worth these inconveniences.
