Asthma and allergy shots
In this entry, I would liketo comment on whether immunotherapy (allergy shots) can help control asthma.
What are allergy shots?
Allergy shots are extractsof one or several allergens that are injected in the skin at gradually increasingconcentrations over weeks to help control hayfever and/or asthma symptoms. Theidea is that by building up exposure to things we are allergic to, our immunesystem becomes ‘tolerant’, and will react less when we come in contact with atrigger. The treatment plan for allergy shots is determined and performed in anallergist’s office.
Allergy shots for hayfeveror asthma can be given for many triggers in the environment, all of which are‘airborne’. These include tree, grass and weed pollen, dust mites, pet dander,and molds. Allergy shots are also given to prevent severe allergic reactionscalled anaphylaxis, mostly for insects such as bees, hornets, and wasps. Whilefood allergy can cause similar severe reactions, allergy shots are not given for food allergies becauseavoidance is the best ‘treatment’, there is risk of causing reactions whengiving allergy shots, and they have been found not to work for food allergy.
Getting allergy shots is asignificant time commitment – coming to the allergist’s office once or twice aweek for the first 4-8 weeks, then twice a month, then monthly during the‘maintenance’ phase. How long it takes to get there depends on the number ofshots needed and how well they are tolerated as the dose is building up.
How well do allergy shots work for allergies andasthma?
There is extensive evidencefrom clinical experience and the scientific literature that allergy shots arevery effective at controlling symptoms from ‘allergic rhinosinusitis’ –hayfever. This includes symptoms in the nose, sinuses, and throat but alsoitchy eyes and skin. In general, they work best if there are fewer allergensand for those allergens that are seasonal (pollens, for example).
Since there is a closeconnection between asthma and allergies (see entry from Summer 2006), allergyshots have been used for a long time in individuals with predominant asthma,and mild ‘hayfever’ symptoms. Unfortunately, for reasons that scientists andimmunologists have yet to uncover, allergy shots do not provide the same degreeof relief from symptoms for asthma as they do for allergic rhinitis. This maybe due to differences in the allergic response in the lungs compared to thenose and sinuses, and/or that the structure and cells of the inner surface ofthe lungs and nasal passages are different. However, most patients who aregetting allergy shots for combined hayfever and asthma will notice that theirasthma gets better along with their hayfever symptoms.
If your asthma is not wellcontrolled despite being on several medicines, you may benefit from addingallergy shots to your treatment regimen. You should talk to your doctor to seeif this treatment might be right for you.
Published On: May 03, 2007