A Guide to Sublingual Immunotherapy in Japan.

Used to treat type I allergies, allergen immunotherapy (AIT) can lead to sustained remission even after treatment cessation. In Japan, sublingual immunotherapy (SLIT) is the only therapeutic option for allergic rhinitis caused by Japanese cedar pollinosis (JCP) and house dust mite (HDM) allergies. Clinical studies have shown that SLIT tablets reduce symptom scores by approximately 30% while maintaining a high safety profile; serious adverse events are rare, and most reactions are mild, local irritations. Japanese multicenter studies have also confirmed the safety of concomitant administration of JCP and HDM SLIT tablets within a five-minute interval. Additionally, JCP SLIT shows cross-efficacy against Japanese cypress pollinosis. While a treatment period of 3-5 years is recommended for long-term efficacy, significant clinical benefits are often observed during the first pollen season. Japan maintains a high adherence rate of approximately 80%, underscoring the importance of proper patient selection and pretreatment education. Thanks to its efficacy, safety, and non-invasive nature, SLIT continues to play a central role in the management of allergic rhinitis in Japan.