Lithium Mouthwash May Reduce Radiation-Induced Oral Toxicity in head and neck cancer patients: Study
A new study published in the International Journal of Radiation Oncology showed that lithium-containing mouthwash significantly reduced the incidence and delayed the onset of severe oral mucositis (SOM), while demonstrating a favorable safety profile among head and neck cancer patients. It also showed potential to alleviate radiation-induced taste dysfunction (TD), suggesting a possible supportive role during radiotherapy.
Oral mucositis is one of the most common and debilitating side effects of radiotherapy for head and neck cancers. The condition causes painful inflammation and ulceration of the mouth lining, often making it difficult for patients to eat, speak, and continue treatment as planned. Taste dysfunction (TD), another frequent complication, further diminishes nutritional intake and overall well-being. Despite supportive care measures, effective preventive therapies remain limited.
The single-institution trial enrolled 175 patients receiving either definitive or postoperative radiotherapy for head and neck cancer. During the phase I portion, researchers established 0.15 mol/L as the optimal concentration of the lithium-containing mouthwash after confirming the absence of dose-limiting toxicity. This dose was subsequently evaluated in the phase II study, where patients were randomly assigned to receive either the lithium mouthwash or a placebo three times daily throughout radiotherapy.
The results showed a significant reduction in the incidence of severe oral mucositis among patients using the lithium-containing mouthwash. Severe OM occurred in 34.2% of patients in the lithium group compared with 52.1% in the placebo group, representing a statistically significant improvement. Moreover, patients receiving the lithium mouthwash experienced a delayed onset of severe mucositis, indicating prolonged protection during the course of radiotherapy.
Patients treated with lithium reported less taste dysfunction during radiotherapy, suggesting the therapy may help protect sensory function that is often compromised by radiation exposure. Preservation of taste could contribute to better nutritional intake, treatment adherence, and overall quality of life during cancer therapy.
The incidence of adverse events was comparable between the lithium and placebo groups, and investigators reported no severe lithium-related adverse events. These findings indicate that the mouthwash was well tolerated, supporting its potential use as a supportive care intervention during radiotherapy. Overall, the findings of this study suggest that lithium-containing mouthwash offers a safe and effective strategy to reduce the occurrence and delay the onset of severe oral mucositis while also showing promise in alleviating radiation-induced taste dysfunction.
Source:
Li, Z., Pei, Y., Zhang, Z., Zheng, S., Li, Y., Wu, Q., Wang, J., Yang, H., Li, R., Zheng, L., Xu, X., & Peng, X. (2026). Effect of lithium mouthwash on oral mucositis and taste dysfunction in head and neck radiotherapy: The phase I/II clinical trial. International Journal of Radiation Oncology, Biology, Physics. https://doi.org/10.1016/j.ijrobp.2026.08.030
