A Lithium-containing Mouthwash Prevention and Treatment of Oral Mucositis and Dysgeusia in Patients Undergoing Radiotherapy

To evaluate the efficacy and safety of lithium-containing mouthwash for prevention and treatment of oral mucositis and dysgeusia in patients undergoing radiotherapy for malignant head and neck tumors.

Inclusion Criteria: Patients pathologically diagnosed with non-metastatic head and neck malignant tumors; Aged 18-80 years; Eastern Cooperative Oncology Group performance status of ≤2; Planning to receive definitive RT or postoperative adjuvant RT; Normal liver, kidney and bone marrow function; Sign informed consent. Exclusion Criteria: Known to be allergic to lithium or other components of mouthwash or severe allergic constitution; Poor oral hygiene and/or severe periodontal diseases; Any previous RT to the head and neck region, Severe kidney disease, severe cardiovascular disease, myasthenia gravis, Parkinson's disease or epilepsy; Recent use or current use of diuretics or other drugs known to interact with lithium; Deemed unsuitable for the study by the investigators (concomitant with any other severe diseases).