Definition
Allergen immunotherapy uses tiny doses of an allergen to lower the body’s reaction to it. There are two types:
- Subcutaneous immunotherapy (SCIT)—injected under the skin
- Sublingual immunotherapy (SLIT)—pills or drops under the tongue
Reasons for Procedure
Allergen immunotherapy is done to lower or stop the body's reaction to an allergen. It may reduce or end the need for allergy medicine. It works best for:
- Severe hay fever
- Life-threatening reaction to insect stings
- Dust mite allergy
- Animal allergy
Insect Bites |
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Possible Complications
Problems are rare, but all procedures have some risk. Your doctor will review problems that may happen, such as:
- Skin redness, swelling, and itching
- Sneezing
- Nasal congestion
- Hives
- Lightheadedness
- Infection at an injection site (for SCIT)
Rare problems may be:
- Throat swelling
- Wheezing or tightness in the chest
- Nausea
Talk to your doctor about ways to manage things that may raise your risk, such as:
What to Expect
Prior to Procedure
Tests will be done to learn which allergens are causing problems. These may be skin prick tests or blood tests. This information will help choose which allergens and doses to use.
Talk to your doctor about all medicines and supplements you are taking. Some may need to be stopped up to 1 week before surgery.
Anesthesia
Anesthesia is not needed.
Description of the Procedure
The allergen will be given in one of two ways:
- Subcutaneous immunotherapy (SCIT): A needle will be filled with a dose of the allergen. Your arm will be cleaned. The injection will be given under the skin of your arm.
- Sublingual immunotherapy (SLIT): Tablets or drops of the allergen are placed under your tongue for 1 to 2 minutes.
You will be given a schedule. It will start with a build-up phase where the amount of allergen is slowly increased. The maintenance phase is when the dose will stay the same, but there may be fewer treatments.
Treatment will need to be repeated over 3 to 5 years.
How Long Will It Take?
A few minutes
Will It Hurt?
You will feel a stinging if your allergen immunotherapy is being given by injection.
Post-procedure Care
At the Care Center
Right after the procedure, the staff will:
- Place a bandage over any injection site
- Watch you for an allergic reaction
At Home
It will take time before the body's reaction to the allergen changes.
Call Your Doctor
Call your doctor if you have:
- Signs of infection, such as fever and chills
- Redness, swelling, pain, bleeding, or discharge from an injection site
- Skin redness, swelling, and itching
- Hives
- Problems breathing
- Nausea
- Lightheadedness
If you think you have an emergency, call for medical help right away.
RESOURCES
American Academy of Allergy, Asthma, and Immunology http://www.aaaai.org
Kids Health—Nemours Foundation http://www.kidshealth.org
CANADIAN RESOURCES
Allergy Asthma Information Association http://www.aaia.ca
Health Canada http://www.canada.ca
References
Allergy shots (immunotherapy). American Academy of Allergy, Asthma, and Immunology website. Available at: http://www.aaaai.org/conditions-and-treatments/library/allergy-library/allergy-shots-(immunotherapy). Accessed November 19, 2019.
Allergy shots. Kids Health—Nemours Foundation website. Available at: http://kidshealth.org/en/parents/shots.html. Updated April 2014. Accessed November 19, 2019.
Allergy shots (subcutaneous immunotherapy). American College of Allergy, Asthma, and Immunology website. Available at: http://acaai.org/allergies/treatment/allergy-shots-immunotherapy. Updated December 28, 2017. Accessed November 19, 2019.
Roberts G, Pfaar O, et al. EAACI Guidelines on Allergen Immunotherapy: Allergic rhinoconjunctivitis. Allergy. 2018 Apr;73(4):765-798.
Subcutaneous immunotherapy for aeroallergens. EBSCO DynaMed website. Available at: https://www.dynamed.com/management/subcutaneous-immunotherapy-for-aeroallergens . Updated June 21, 2018. Accessed November 19, 2019.
Sublingual immunotherapy. EBSCO DynaMed website. Available at: https://www.dynamed.com/management/sublingual-immunotherapy . Updated May 31, 2019. Accessed November 19, 2019.
Revision Information
- Reviewer: EBSCO Medical Review Board James P. Cornell, MD
- Review Date: 09/2019
- Update Date: 09/11/2020