Immunotherapy, commonly referred to as “allergy shots,” is a safe and effective treatment for patients with allergies. The most common allergens treated include house dust mites, cat dander, grass, and mold.
What are allergy shots?
When medications fail to adequately control allergy symptoms and it is difficult or impossible to avoid triggers, an allergist may recommend immunotherapy or “allergy shots.” This treatment consists of a series of injections containing small amounts of the substances to which the person is allergic. After completing a course of allergy shots, 80 to 90 percent of patients show fewer allergy symptoms, and in many cases, their allergies are completely resolved. Allergy shots can be given to those with allergic rhinitis, seasonal allergic conjunctivitis (nose and eyes), asthma, and insect sting allergies.
How does immunotherapy work?
Immunotherapy works by reducing your sensitivity to specific allergy triggers. The vaccine is injected under the skin in gradually increasing doses, and the body responds by developing immunity or tolerance to the allergens. As a result of these immune changes, immunotherapy can reduce allergy symptoms when the patient is exposed to the allergens included in the vaccine.
Who is a candidate for allergy shots?
Immunotherapy can be offered to anyone over the age of seven who has types of allergies that do not improve with treatment and who have a positive allergy test to specific allergens. There is no risk that prevents a pregnant woman from receiving this type of treatment; it is safe. However, caution should be exercised with dosing, and treatment should not be started during pregnancy.
What is expected after each shot?
Allergy shots are given in the allergist’s office. You will remain in the office for 20 to 30 minutes after receiving the injection in case you have a severe reaction to the allergy shot. Redness and warmth at the injection site are common but resolve shortly.
How long do I need to take allergy shots?
Allergy patients should not expect immediate improvement. It may take 4-6 months before noticeable improvement and relief of allergy symptoms occur, and it may take up to 12 months to achieve the full desired benefit. After reaching the maintenance dose, the interval between injections will be changed to 2-4 weeks, depending on the patient’s sensitivities. After achieving good results for four years, it may be possible for the patient to stop allergy shots if repeated skin testing indicates that they are no longer sensitive to the allergens. Treatment lasts 3 to 5 years, after which the patient continues to benefit for 5 to 10 years or more, even after stopping the shots.
What is the difference between immunotherapy injections and sublingual immunotherapy (drops under the tongue)?
Immunotherapy has been given by injection for more than 60 years, and many studies have proven its effectiveness. Several studies published in the last five years have shown that high-dose sublingual immunotherapy, where several drops of allergen extract are held under the tongue for a few minutes and then swallowed, is also effective.
How effective is immunotherapy?
Allergy shots are effective for treating allergic asthma and allergic rhinitis. The shots relieve symptoms in those sensitive to pollen, animal dander, dust mites, mold, and cockroaches.
What are the main side effects of immunotherapy?
If complications or allergic reactions develop, they usually occur within 20 minutes; however, symptoms and complications can develop up to two hours after the injection. Side effects include:
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Generalized itching, swelling, red eyes, hives, and pain at the injection site.
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Less common side effects are low blood pressure, asthma, or difficulty breathing. In rare cases, especially due to overdose or if the patient has a serious lung condition, severe reactions can occur that may be life-threatening.
Who should not take allergy shots?
Allergy shots should not be given to:
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Those with a recent heart attack, unstable angina, any other heart disease, or those taking beta-blockers.
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Most doctors do not give allergy shots to children under 5 years of age.
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Those with an immune system disease such as AIDS.
