Allergy shots can reduce your reaction to allergens, which can result in fewer or less severe symptoms. They may also prevent children who have allergic rhinitis from getting asthma. Recommendations on when to get allergy shots vary.
When you get allergy shots (immunotherapy), your allergist or doctor injects small doses of substances that you are allergic to (allergens) under your skin. This helps your body "get used to" the allergen, which can result in fewer or less severe symptoms of allergic rhinitis.
Your allergist will use an extract of grass, weed, or tree pollen; dust mites; molds; or animal dander for allergy shots. You must first have skin testing to find out which allergen you are allergic to.
Your allergist injects under your skin a solution of salt water (saline) that contains a very small amount of the allergen(s). You gradually receive more of the allergen in the shots.What To Expect After Treatment
You receive allergy shots in your allergist or doctor's office. They may have you stay in the office for a short time after you get the shots, in case you have a severe reaction (anaphylaxis) to the injected allergens.
Redness and warmth at the shot site are common. But these go away after a short period of time.Why It Is Done
Allergy shots can reduce your reaction to allergens, which can result in fewer or less severe symptoms. They may also prevent children who have allergic rhinitis from getting asthma.2 Recommendations on when to get allergy shots vary, but in general you and your doctor may consider them when:Allergy symptoms are severe enough that the benefit from the shots outweighs the expense and the time spent getting the shots. You are allergic to only a few substances, and they are hard to avoid. Avoiding allergens and using medicine do not control symptoms, or you have to take medicine all the time to control symptoms. Side effects of medicines are a problem. You want a treatment for the cause of your allergy, rather than treatment for just the symptoms. You have another condition that is being affected by allergic rhinitis, such as asthma. You want to lower the chance that you will develop asthma. How Well It Works
Allergy shots are effective in treating allergic rhinitis and allergic asthma.2 The shots reduce symptoms in those allergic to pollens, animal dander, dust mites, mold, and cockroaches.2 Experts do not know how long allergy shots work after you stop getting the shots.2 Some people may not have their allergies return. Others may have allergies return within a few years.
Although you still need to avoid allergens, you may be able to use less medicine or stop using medicines.References Citations Nelson HS (2003). Immunotherapy for inhalant allergens. In NF Adkinson Jr et al., eds., Middleton's Allergy Principles and Practice, 6th ed., vol. 2, pp. 1455'1473. Philadelphia: Mosby. Joint Task Force on Practice Parameters (2010). Allergen immunotherapy: A practice parameter third update. Journal of Allergy and Clinical Immunology, 127(1, Suppl): S1'S55.