A Double-blinded, Placebo-controlled Study to Evaluate the Efficacy and Safety of Oral Pilocarpine for Treatment of Post-irradiation Xerostomia in Taiwanese Patients with Head and Neck Cancer

Abstract

Many head and neck cancer patients suffer from xerostomia after radiotherapy. We designed a double-blinded, placebo-controlled, multicenter study to evaluate the efficacy and safety of oral pilocarpine for treatment of post-irradiation xerostomia in head and neck cancer patients. In this study, 96 patients were recruited. The dose of external beam radiation was at least 40 Gray in 4 weeks. Patients received 5 mg oral pilocarpine hydrochloride three times a day for 12 weeks. For determining efficacy, subjective xerostomia was assessed using a visual analog scale (VAS) xerostomia questionnaire that measured oral dryness, mouth and tongue comfort, speaking without fluid, the need for oral comfort agent, chewing and swallowing, and the ability to sleep. Twentynine patients completed the experiment in the study group, and 36 patients in the control group. The xerostomia of patients in both groups improved (11.1%~37.9%), and there was no significant difference except in the ability to sleep (p = 0.049). The data of safety showed that there were no statistically significant differences between these two groups. However, the study group experienced increases in sweating and urinary frequency. Administration of 5 mg of oral pilocarpine three times a day for treatment of post-radiotherapy xerostomia is effective and safe for Taiwanese patients with head and neck cancers.