Effect of Oral Pilocarpine on Post-Irradiation Xerostomia in Head and Neck Cancer Patients: A Single-Center, Single-Blind Clinical Trial
Imjai Chitapanarux MD*, Pimkhuan Kamnerdsupaphon MD*, Ekkasit Tharavichitkul MD*, Yupa Sumitsawan MD**, Pichit Sittitrai MD**, Tienchai Pattarasakulchai MD**, Vicharn Lorvidhaya MD*, Vimol Sukthomya MD*, Nantaka Pukanhaphan BSc*, Patrinee Traisatit PhD***
Affiliation : * Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University, Chiang Mai ** Department of Otolaryngology, Faculty of Medicine, Chiang Mai University, Chiang Mai *** Department of Statistics, Faculty of Science, Chiang Mai University, Chiang Mai
Objective : The authors determined the efficacy and safety of oral pilocarpine tablet in symptomatic relief of
post-radiation xerostomia in head and neck cancer patients.
Material and Method: Thirty-three radiation-induced xerostomia patients were enrolled in a single-blind
method to receive placebo 1-tablet three times daily in the first month and then oral pilocarpine (5 mg)
1-tablet three times daily for the next three months. Patients were evaluated for subjective symptomatic relief
of xerostomia using questionnaires. Objective findings of xerostomia were also evaluated at the same time by
two radiation oncologists.
Results : All 33 patients had received radiotherapy doses at least 4000 cGy to the parotid glands. Improvement
of xerostomia symptoms was observed, with a mean total subjective xerostomia score improvement at the first
4 weeks of oral pilocarpine treatment (p = 0.001), and later throughout the present study. Objective xerostomia
score also showed statistically significant improvement at the same time point. Adverse effects of pilocarpine
included sweating, nausea, palpitation, and tearing, with sweating as the most common side effect. Adverse
effects of placebo included mild headache, nausea, and vomiting.
Conclusion : Oral pilocarpine was effective and well tolerated in the treatment of radiation-induced xerostomia
symptoms.
Keywords : Pilocarpine, Radiation-induced xerostomia, Head and neck cancer
