Phytochemicals as therapeutic strategy for oral mucositis in cancer patients

Oral mucositis (OM) is a severe toxicity of cancer therapy that often leads to treatment delays or interruptions, compromising patients’ oral functions, nutrition, quality of life and, ultimately, disease outcome. Although OM is a frequent and limiting condition, there are few approved approaches available and none of them can avoid completely its onset. The primary objective of this review was to critically present findings from randomized controlled clinical trials investigating the use of medicinal plants and bee products as therapeutic strategy for OM induced by radiotherapy or chemotherapy regimens, while evaluating reports on the phytochemical characterization of the products used as well. Analysis revealed that several studies lacked information on the phytochemical composition of the products used, and variations in this composition may influence the outcomes of a clinical trial. This review presents the main bioactive constituents for each natural product investigated in clinical trials for OM alleviation and indicates analytical methods to determine them. A secondary objective of this review was to assess toxicity outcomes of the use of these products. Most studies report toxicity outcomes evasively, highlighting the need for more thorough reporting that may guide the development of safer pharmaceutical forms. Overall, strengths and pitfalls of the reviewed studies are presented and discussed. In conclusion, this review may support future research to strengthen the evidence base for the therapeutic use of medicinal plants and bee products to broaden OM management strategies for cancer patients.