Zinc sulphate for oral mucositis: An updated narrative review of existing and recent evidence

Oral mucositis (OM) refers to the damage of the oral mucosa as a result of cancer treatments. It is a common and debilitating condition that significantly impacts patients’ quality of life. Currently, a limited number of safe and effective preventive options is recommended for management of OM. Among the potential interventions for management of OM is zinc, an affordable nutritional supplement, which is typically well-tolerated and rarely causes serious side effects. In recent years, many publications have emerged, which investigated the efficacy of several forms of zinc in OM treatment. One of these forms is zinc sulfate, which can be administered as a mouthwash or taken in the form of a capsule. The most recent 2020 update of the Multinational Association of Supportive Care in Cancer/International Society for Oral Oncology (MASCC/ISOO) Clinical Practice Recommendations, published recommendations on zinc in OM treatment as no guideline possible (NGP) due to lack of Level I and II Evidence. Since then, several new randomized controlled trials (RCTs) have been published, which were not included in the earlier analyses. These studies suggest positive outcomes for the use of zinc in managing OM. Consequently, the aim was to conduct a comprehensive review of all available evidence up to August 2024 regarding the use of zinc sulfate in cancer treatment. Based on 13 studies published between 2004 and 2024, the current review suggests that zinc sulfate may impact future treatment guidelines for cancer therapy-induced oral mucositis. However, further large-scale, high-quality randomized trials are necessary to validate these results.