Allergy shots are a treatment option for many patients with chronic allergies. This fact sheet provides general information about what allergy shots are, who can take them, and what’s involved in getting the shots. We hope that this material helps you better understand how allergy shots can help manage allergies. Please keep in mind that this information is not meant to take the place of medical advice from your physician.
When 32-year-old Ben moved to the east coast of the United States from the Pacific Northwest, he soon developed a classic case of seasonal allergies. After a few years, his allergies got worse, and seemed to hang on year round. Over-the-counter medications helped at first, but after a while he needed to use several prescriptions to help cope with the increased symptoms. Finally, he saw an allergist for testing and treatment options. Within 11 months of starting allergy shots, Ben’s allergy symptoms had decreased significantly and he was able to reduce his use of other medications.
What are allergy shots?
The term “allergy shots” is the general name given to a medical treatment for allergies known as immunotherapy. Immunotherapy (the shots) is given in a series over a period of time. Allergy shots help individuals who are allergic to specific substances (“allergens”) develop a tolerance for those allergens. This increased tolerance helps minimize any subsequent allergic response when they come in contact with the allergens.
What is an allergy?
An allergy is an adverse reaction from an immune response to something that contacts the body, is inhaled, or ingested. The reactions include sneezing, wheezing, cough, itching, skin rashes, stomach pain, diarrhea, or even a fall in blood pressure, which can cause dizziness or passing out. With proper management and education, people with allergies can lead healthy, normal lives.
Who is eligible for immunotherapy?
To help determine if you are a good candidate for allergy shots, your physician will consider two key factors:
- What are you allergic to
- How well avoidance and other allergy treatments are controlling your symptoms
The first and most effective treatment for all allergic disease is avoidance. For example, patients allergic to dust mites can reduce their exposure with special encasings for mattresses and pillows. Patients allergic to pets may have to find a new home for the pets. Some allergens, however, are difficult or impossible to avoid. For example, one cannot avoid exposure to pollen in the outdoor air, and insect stings can happen unexpectedly even if one is trying to avoid being stung.
People who are allergic to allergens and cannot avoid pollen and mold or can only partially avoid animals, dust mites, stinging insects are the best candidates for immunotherapy. Patients who must use multiple medications to manage allergy symptoms also are considered for immunotherapy. Finally, patients with potentially life-threatening allergies, such as those to stinging insects, should strongly consider immunotherapy. Although allergic reactions to food (such as peanuts) and medications (such as penicillin) are also potentially life threatening, allergy shots are not currently available for these allergies. The treatment for food and medication allergies is strict avoidance, and being prepared to treat accidental exposure.
If respiratory allergy symptoms are being effectively controlled by medications such as steroid sprays and antihistamines, particularly if they affect the patient for only a brief period each year, allergy shots, while they may be effective, may simply not be worth the time, expense, and risk. On the other hand, if symptoms are not controlled with medications or if the medications need to be taken year round, allergy shots may be an effective alternative.
Additional considerations for immunotherapy include the age and health of the patient. Patients at either end of the age spectrum may not be good candidates for allergy shots because they may have not yet developed all their allergies (very young children), or will soon naturally lose their allergies (older adults).
An important consideration . . . Patients with other health conditions such as severe asthma or heart disease may also not be eligible for immunotherapy, since they might not be able to survive the occasional severe generalized (“systemic”) allergic reactions, which may be caused by the shots themselves.
What is the process for starting allergy shots?
While many types of physicians take very good care of patients with allergies when allergy shots are being considered, physicians with special training and certification in allergies (allergists) must evaluate patients. Your allergist must first determine if you have allergies and if so, what you are allergic to. Skin testing normally does this.
Skin testing involves placing a tiny drop of an extract from various common allergens on your skin (either on your forearm or your back). Then, a light prick is made through the drop with a sterile pricking device. Typically you would be tested for about 50 such substances. Although being pricked 50 times may sound uncomfortable, modern skin test devices are often made of plastic and just barely break the skin. The vast majority of children and adults do not describe the pricking as uncomfortable, and certainly not as painful. Sometimes a procedure known as intradermal (under the skin) testing is used, where a small amount of an allergen is injected into the outer layer of the skin on the forearm. This procedure is rarely done for airborne allergens (like pollen, mold, animal dander, or dust mites), but is necessary for some allergens like stinging insects. Intradermal testing does involve some discomfort, but is typically done for only a handful of allergens.
If you are allergic to any of the allergens placed on your skin, you will develop redness, swelling, and perhaps itching at the test site within 20 minutes. The size of these reactions are then measured and recorded. The reactions disappear by themselves over about another 20 minutes.
After your allergist uses the skin testing to identify specific allergens that cause you to have an allergic reaction, you and your physician will discuss the option of treatment with immunotherapy — the allergy shots — based on the considerations outlined above. No one needs to go on allergy shots. Whether or not you get allergy shots is up to you. Like any treatment, there are potential benefits, but also potential risks. The decision is yours.
How are allergy shots administered?
A specialized mix of allergenic extracts is prepared just for you, based on your allergies as determined by your history and skin tests. You begin with shots once or twice a week, until you reach a “maintenance dose” or immunotherapy. This process usually takes four to six months after which most patients will begin to have relief of their symptoms. If symptoms do not improve, the use of allergy shots for your condition should be reconsidered. For those with a good response to the shots (at least 85% of properly selected patients), maintenance doses are then given on a monthly basis for a total of three to five years. After this time, the shots can be stopped and the improvement in symptoms is usually long lasting or permanent. If the shots are discontinued too soon, the symptoms will likely return.
Is there a risk involved in getting allergy shots?
Not surprisingly, since immunotherapy involves injecting you with substances to which you are known to be allergic, there is some risk of an allergic reaction to the shots themselves. These sudden severe reactions can even be life threatening. Of the approximately 10 million allergy shots given in the United States each year, it is estimated that there may be four deaths due to shot reactions almost all in patients with poorly controlled asthma. For this reason, allergy shots can only be administered where a physician and emergency medical equipment are physically present. Also, patients must wait at the physician’s office for 20 to 30 minutes after each shot to be sure they are not having such a reaction. Under no circumstances can allergy shots be given at home.
Do allergy shots help control asthma?
Allergy shots are usually given for allergic rhinitis (“hay fever”), the itchy, watery eyes, runny nose, and sneezing people who are allergic to airborne allergens get when exposed to these allergens. The shots are very effective for these symptoms.
The same allergens that cause allergic rhinitis can also trigger asthma symptoms, and immunotherapy may help. It is important to remember though that many other things trigger asthma episodes, such as exposure to irritants, like cold air and smoke; exercise; and the common cold. Allergy shots will not help with these asthma triggers.
Does health insurance cover allergy shots?
Most health insurance plans probably provide some level of coverage for immunotherapy. Check with your insurance carrier for details. Some things you may want to find out might include:
• Do you need a referral to an allergist specialist from your internist, family physician, or pediatrician?
• If you had allergy shots when you were younger, and now are experiencing allergies again after a period without treatment, does the insurance provider consider this a pre-existing condition? If so, what coverage is offered for pre-existing conditions?
• How long does the insurance cover the shots? Are there a specified number of shots that will be covered within a certain time frame?
The information provided in this fact sheet should not be a substitute for seeking responsible, professional medical care.
Reprinted with permission from “Asthma and Allergy Answers,” the patient education library developed by the Asthma and Allergy Foundation of America.