WHAT YOU SHOULD KNOW BEFORE YOU BEGIN ALLERGEN IMMUNOTHERAPY (“Allergy Shots”)
What is immunotherapy (allergy shots)?
Immunotherapy (allergy shots) is a proven method to treat asthma and allergic rhinoconjunctivitis (eye/nose allergies). This is accomplished by injecting increasing doses of the things to which one is allergic, such as dust mites, cat/dog, pollen and mold. Over time, this consistent allergen exposure presented to the immune system in a different way than normal exposure, decreases the person’s sensitivity to their allergen, allowing increased exposure without triggering allergy or asthma symptoms. As one becomes less allergic, the need for medication generally decreases. Allergy shots make one less allergic over time, which is fundamentally different from medication, which may control symptoms but does not alter the underlying degree of allergy. Many people consider allergy shots a more natural way to treat the underlying allergies, then the long-term use of medication.
What is the usual treatment schedule?
There are two phases to allergy shots: build-up and maintenance.
Build-up phase:
During the build-up phase, each time that the allergy shots are administered, the dose is increased slightly, as long as the previous injection was well tolerated. The traditional buildup injection schedule is to receive the allergy injections once a week until the top dose is achieved, which usually takes approximately 6-7 months. Top dose is achieved more quickly if injections are initially administered twice a week. Alternatively, there is an accelerated buildup injection schedule known as “cluster immunotherapy “which reduces the total number of allergy injections administered during the buildup phase and the length of time required to achieve the top dose. This is accomplished by “clustering” several allergy injection visits into extended visits during the beginning of the immunotherapy build-up phase.
Maintenance phase:
Once the top dose is achieved (often even prior to achieving top dose) one’s allergy and/or asthma symptoms usually have improved. However, if immunotherapy was stopped once the top dose was achieved, the benefit would be short-term, and our goal is long-term benefit. In order to achieve long-term benefit, we continue to administer the top dose of the allergy shots, increasing the time interval between injections. The injection interval is generally increased to a four-week interval. The top dose is administered once every three or four weeks until immunotherapy is stopped. To maximize the likelihood of continued benefit even after the allergy shots are stopped, the injections are continued for an average of 3-5 years once the top dose has been achieved. Typically, at either 6- or 12-month intervals, a new set of immunotherapy (allergy shot) vials will be made. For your safety, the dose you receive from the new vial will be lowered, and you will need to build back to the top dose over a few visits.
What happens if I miss an allergy shot visit?
People often miss an allergy shot visit due to travel, vacation or illness. This does not cause a problem since the dose of the next allergy injection can be modified to accommodate the missed visit.
How well does the treatment work?
Most patients are very pleased with their decrease of symptoms. Allergy shots diminish the degree of sensitivity to one’s allergic triggers. Some patients completely lose their sensitivity, while others experience a significant decrease of their sensitivity, but in some circumstances may still develop some allergy symptoms if sufficient exposure to their allergens occurs. The current extracts utilized for the injections are vastly superior to what was available in the past.
What are the risks of allergy shots?
Allergy shots have been administered for more than 100 years. Therefore, we are confident that there are no long-term side effects. However, each time that one receives an allergy injection there is a small risk of a reaction. Some patients experience some redness, itching or swelling at the injection site, especially as higher doses are reached. These reactions are undesirable, but not dangerous. The likelihood of these symptoms can be minimized by administering an anti-histamine prior to coming to the office for the allergy injection. A small minority of patients may experience a generalized allergic reaction, which could include hives/swelling, sneezing/wheezing or abdominal symptoms. In very rare situations patients have developed faintness due to a drop of blood pressure or generalized life-threatening anaphylaxis. In consideration of this risk, all patients must remain in the physician’s office for 30 minutes after administration of the allergy injections.
When should I not receive my allergy injection?
Certain conditions increase the risk of adverse reactions, such as if you are experiencing an exacerbation of asthma or significant allergy symptoms. Respiratory infections other than a minor cold may also increase the likelihood of a reaction. The concurrent use of a “beta blocker” medication, commonly prescribed for blood pressure or glaucoma is a relative contraindication to receiving allergy injections. If a beta blocker medication is prescribed during your course of allergy shots, schedule an office visit with your allergist to discuss this issue prior to receiving your next allergy injection.