Allergy shots are one type of treatment for asthma that may benefit those with allergies and asthma, called allergic asthma. Also called immunotherapy, allergy shots are not an asthma cure like an injection of antibiotics might cure an infection. Instead, allergy shots work a bit more like a vaccine.
Allergy shots for asthma actually contain a very small amount of an allergen (something you're allergic to). Over time, the dose is increased. By exposing you to greater and greater amounts of the allergen, your body is likely to develop a tolerance to it. If the treatment goes well, your allergic reaction will become much less severe.
Occupational asthma is asthma caused by, or worsened by, exposure to substances in the workplace. These substances may cause asthma in one of 3 ways:
An allergic reaction (like people with allergies who develop allergic asthma)
An irritant reaction (like a person that reacts to smoking with asthma)
A reaction which results in chemicals that occur naturally in the body, building up in the lung and resulting in an asthma attack
Examples of occupational asthma -- also called work-related...
Allergy shots can reduce the symptoms of allergies and prevent the development of asthma. Allergy shots also appear to help people who already have asthma, although there is some debate about this. One study found that allergy shots for asthma were as effective as inhaled steroids in reducing asthma symptoms.
What to Expect From Allergy Shots for Asthma
Before you get allergy shots for asthma, your doctor will want to do allergy testing. This is a way of finding out which allergens affect you. It will probably involve skin testing, in which a small amount of the allergen is scraped onto or injected under your skin. Allergy shots aren't available for every kind of allergy.
Allergy shots for asthma include shots for:
Once you and your doctor have discovered which allergens affect you, the next step is to get the shots. The frequency of the injections varies, but you might get them once or twice a week for the first three to six months -- or until you reach the maximum dose. After that, you might only need maintenance injections every two to four weeks. This might continue for three to five years.
Although some people feel asthma symptom relief from their allergy injections quickly, it may take up to a year for others. In some people, allergy shots have no effect.
Who Needs Allergy Shots for Asthma?
Allergy shots are not right for everyone. It may not be safe for people who have uncontrolled asthma or other health conditions, such as heart disease. It may also not be a good idea for people taking certain medications, such as beta-blockers. Allergy shots for asthma are not used in children who are under age 5.
Allergy shots for asthma might be considered for people who:
Have the time and dedication to undergo a treatment that can last many months or years
Cannot take certain asthma medicines, such as bronchodilators or want to avoid using them
Risks of Receiving Allergy Shots for Asthma
Allergy shots for asthma do have risks. The most common side effects are redness and swelling at the site of the injection.
More severe reactions are less common. Very rarely, allergy injections can even lead to anaphylactic shock, which can be fatal. This is why you should always get these shots in the presence of experts who can control any adverse reactions in the event of an asthma emergency. Your asthma doctor might want to keep you under observation for about 30 minutes after the injection to watch for any ill effects.
There is an new alternative to shots called Sublingual Immunotherapy or “SLIT” that is promising and now available. Instead of a shot, the medication is dissolved under your tongue. Ask your doctor if you are a candidate for SLIT.
American Academy of Asthma, Allergy, and Immunology: "Tips to Remember: What are Allergy Shots?"
Grayson, M. and Holtzman, M. ACP Medicine, 2005.
Stokes, J. and Casale, T. American Journal of Medicine, 2006.
Johns Hopkins Medicine: "Sublingual Immunotherapy."