Allergy Shots - The Changing World Of Allergy Treatments: Allergies

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Allergy shots

Allergy shots

Allergy shots, also known as immunotherapy, have been around for a long time. They are designed to decrease your sensitivity to the triggers that set off your allergies. Advances have identified the proteins that are the main allergens in pollens and dander. This means better standardization of allergy extracts and more accurate dosing than was possible previously.

Immunotherapy works by injecting small and increasing amounts of allergen over regular intervals. Typically, this means weekly injections while the dose is increased (three to six months) and then monthly injections for three to five years. Some allergists use “rush” immunotherapy, in which multiple increasing doses are given in a single day. This allows for maintenance doses to be reached more quickly, but has a greater risk for side effects.

The treatment can be very effective for allergic rhinitis and allergic conjunctivitis. It is the treatment of choice for life-threatening allergies to stinging insects, and it may help in the treatment of allergic asthma. There is no way yet of using it safely for food allergies.

The big drawback of immunotherapy is it could trigger a potentially serious allergic reaction, including an asthma attack or anaphylaxis. Modern allergy extracts and dosing schedules reduce the risk for a serious reaction, but your doctor will still require you to stay in his office for 30 minutes after each shot, just in case. And you should never have an allergy shot if your asthma is not well controlled.

Last updated:	August 21, 2006
Reviewed By:	Faculty of Harvard Medical School