Traditional Chinese Medicine Oral Liquids and Mouthwashes for Radiation-induced Oral Mucositis in Head and Neck Cancer Patients

The aim of this clinical trial is to evaluate the efficacy and safety of combining a traditional Chinese medicine (TCM) oral liquid with a mouthwash in reducing the incidence, duration, and severity of mild-to-moderate radiation-induced oral mucositis (RIOM). The study addresses two main questions: (1) whether the combined TCM oral liquid and mouthwash can effectively mitigate RIOM and lower the incidence of severe RIOM, and (2) whether their use is associated with adverse events in patients receiving radiotherapy. Participants will begin treatment on the first day mild-to-moderate RIOM (RTOG grade 1-2) occurs during radiotherapy. They will take Qingying oral liquid four times daily and use a modified Da Huang-Huang Lian Xiexin mouthwash six times daily in combination, or receive a matching placebo. The treatment will continue until two weeks after radiotherapy. After each administration, patients must avoid eating, drinking, or performing oral hygiene for at least 1 hour to maximize mucosal contact time. The trial will compare the intervention and placebo groups to determine the potential benefits of the combined regimen for managing RIOM.