A randomized phase III prospective trial of bethanechol to prevent radiotherapy-induced salivary gland damage in patients with head and neck cancer.

The aim of this study was to verify whether the use of bethanechol during radiotherapy (RT) for head and neck cancer (HNC) prevents radiation-induced xerostomia and salivary flow reduction. Patients that would begin RT were randomly allocated into bethanechol (group 1) or artificial saliva (group 2). Whole resting saliva (WRS) and whole stimulated saliva (WSS) were collected from all the patients at the following four stages: baseline, during, immediately after, and at least two months after the end of RT.