Immunotherapy, or ?allergy shots,? may help prevent the development of asthma in children with seasonal allergies, according to a study published in the Journal of Allergy and Clinical Immunology. Researchers found a clear link between allergies and asthma. Allergic rhinitis (hay fever or seasonal allergies) frequently precedes the development of asthma.
More than 70% of asthma patients report having nasal symptoms, and about 20% of patients with allergic rhinitis develop asthma. Up to 50% of seasonal allergy sufferers experience bronchial hyperre-sponsiveness (irritated airways) during pollen season.
In this study, 205 children, each with a history of allergy to birch and/or grass pollen, were randomly assigned to one of two groups, the immunotherapy group or the control group. All children were given an initial evaluation to determine the severity of their allergies and whether or not they had asthma. After this evaluation, the immunotherapy group began treatment?weekly injections for the pollen they were allergic to followed by maintenance doses every 6 weeks for a total of 3 years. The control group received no treatment. All children were allowed to take medications to alleviate allergy and asthma symptoms.
Among the 151 children who did not have asthma before treatment, fewer children in the immunotherapy group developed asthma than in the control group. After 3 years of treatment, bronchial hyper-responsiveness scores improved in both groups, but the improvement was more significant in the immunotherapy group.