New efficacy of LTRAs (montelukast sodium): it possibly prevents food-induced abdominal symptoms during oral immunotherapy

The aim of the study was to elucidate whether leukotriene receptor antagonists (LTRAs) can prevent severe allergic reactions, which occur during oral immunotherapy (OIT) in children with food allergies. Five children with food allergies [3 allergic to hen's egg (HE), 1 to wheat, and one to cow's milk (CM); aged between 7 and 12 years; median, 8.5 years] who were started on LTRAs during OIT were retrospectively selected from among 63 children undergoing OIT. In the rush phase, after the administration of the initial dose which was set in open food challenge test, the subsequent doses were increased by approximately 1.2 times of the previous dose and were administered every 2 hours, 4 times a day. The target doses of hen's egg, wheat (udon noodle), and cow's milk in the rush phase were 50 g, 200 g, and 200 ml, respectively. The ingestion of the target dose was continued at home every day for at least a year in the maintained phase.Four participants experienced intractable abdominal pain during the rush phase; therefore, the loading dose was not increased in these children. However, the administration of LTRAs prevented their symptoms, resulting in the completion of the rush phase. One participant also experienced intractable abdominal pain during the maintenance phase. After receiving LTRAs, the target dose was able to tolerated. The findings from this retrospective study suggest that the administration of LTRAs is useful for the prevention of adverse allergic reactions such as abdominal pain during OIT.