Objectives: A survey was conducted to investigate the usability and safety of fentanyl sublingual tablets (FST) and to examine problems associated with their proper use.

Methods: Subjects were 18 cancer inpatients who received FST for breakthrough pain in their pharmacological cancer pain management. Changes in the pain score and the occurrence of adverse effects (nausea, vomiting and somnolence) were compared before and after FST administration.

Results: The pain score before FST administration was 6.4±2.4, and this was significantly improved to 3.4±2.8 at 30 min after administration (p<0.01). Somnolence occurred significantly more often 30 min and 2 h after FST administration than immediately before administration (p<0.05). There were no differences in the occurrence of nausea and vomiting before or after FST administration. Nine patients receiving FST therapy developed xerostomia, but there were no significant changes in the pain score or occurrence of adverse effects while they had xerostomia.

Conclusion: It is essential to observe the oral condition to judge whether FST therapy is indicated, and FST should be administered after providing sufficient oral care. The results indicate the possibility of increased occurrence of somnolence as an adverse effect.