Background: Subjects with head and neck cancer (HNC) often experience post-treatment side effects. particularly radiation-induced oral mucositis (RIOM). This study aimed to explore the association of Chinese herbal medicine use with the sequent risk of RIOM among them. Methods: This cohort study used a nationwide health insurance database to identify subjects newly diagnosed with HNC. https://parisnaturalfoodes.shop/product-category/regenerlife/