Allergen Immunotherapy (AIT) FAQ (Frequently Asked Questions)

This information should be read and understood before signing the ASCIA consent form, prior to commencing allergen immunotherapy (AIT) to aeroallergens or venoms.

pdfASCIA PCC Allergen Immunotherapy FAQs 2020139.08 KB

pdfASCIA Consent Form AIT 202097.49 KB

What is allergen immunotherapy?

Allergen immunotherapy changes the way the immune system reacts to allergens, by switching off allergy. AIT involves the regular administration of gradually increasing doses of allergen extracts, usually over a period of years. This results in tolerance to allergens, with fewer or no symptoms. Three years of AIT can result in five to ten years of benefits. Symptoms may return after this time.

What conditions can allergen immunotherapy help?

Venom allergy immunotherapy:

Aeroallergen immunotherapy:

What should I expect?

How often are allergen immunotherapy injections given?

How often is sublingual allergen immunotherapy taken?

Sublingual allergen immunotherapy extracts are usually taken on a daily basis.

Common methods for taking the allergen extracts:

Are there any potential reactions to allergen immunotherapy injections?

Localised swelling at the site of the injection can be treated with non-sedating oral antihistamines or ice packs and if painful, Paracetamol.

More serious reactions (such as anaphylaxis) are uncommon. However, predicting who might have serious reactions is difficult. Patients are normally advised to:

It is important to inform your doctor about any reactions you may have experienced after your last injection and any new medications you are taking (such as eye drops, new heart/blood pressure tablets), or if you become pregnant.

Patients who are pregnant (or planning to become pregnant) are not routinely commenced on AIT until after they have given birth. If the patient is on maintenance doses of AIT and then becomes pregnant, the injections can be continued (unless the patient wishes to stop), but the supervising specialist must be contacted to discuss relevant safety issues.

Are there any potential reactions to sublingual allergen immunotherapy?

Common side effects include irritation, minor swelling or itching inside the mouth, and stomach upset/nausea. This can be controlled by temporarily reducing the dose or taking a non-sedating antihistamine beforehand. These side effects generally resolve after the first few weeks.

The risk of potentially dangerous side effects arising from this form of treatment, such as difficulty breathing, is extremely low.

Is there anything you can do to reduce the side effects from allergen immunotherapy?

Simple precautions may reduce the risk:

Are there cases when allergen immunotherapy should not be given?

What are the costs of allergen immunotherapy?

© ASCIA 2020

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ASCIA resources are based on published literature and expert review, however, they are not intended to replace medical advice. The content of ASCIA resources is not influenced by any commercial organisations.

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Content created February 2020