Allergy immunotherapy can reduce children's hay fever over time

What the research found

Australian specialist guidance says allergen immunotherapy changes how the immune system reacts to pollen and dust mite. It usually takes at least three years. It can then give five to ten years of tolerance, with fewer or no symptoms. A 2018 European guideline, informed by a systematic review and meta-analysis, calls it the only treatment that targets the underlying cause and says it may modify the disease.

A 2024 paper reported that immunotherapy is highly effective for seasonal pollen allergy, and that three years of treatment gives long-term benefit. It also reported that house dust mite tablets are effective for year-round mite-driven hay fever in adults and children. Long-term results for the mite tablets have not yet been explored. In children with seasonal hay fever, injections and under-the-tongue pollen treatment reduced asthma symptoms and asthma medicine needs.

A 2025 real-world study of 11,036 children and teens with hay fever, some with asthma, compared treated and matched untreated children over nine years using medicine prescriptions. It was not a trial. Its authors note that long-term real-world data in children remain limited. A 2023 meta-analysis compared injections and under-the-tongue treatment in children with hay fever.

What it doesn’t mean

• Immunotherapy is not a first step. Australian guidance says it is often recommended when symptoms are severe, when the trigger is hard to avoid (such as grass pollen), or when medicines do not help or cause side effects. A specialist usually starts it.
• Immunotherapy can cause side effects. The 2023 meta-analysis looked at treatment-related adverse events in children, and Australian guidance says some heart, blood pressure and glaucoma medicines can increase the risk of side effects. Asthma should be stable before starting, and treatment is delayed if asthma flares.
• Children's hospital advice says avoiding triggers is the best way to prevent and reduce hay fever symptoms, and medicines can help manage them. Talk to your GP about whether a referral to an allergy specialist makes sense for your child.