Fentanyl buccal tablets have a long-standing position in the treatment of breakthrough pain. This publication reviews the available literature from 2010–2021 on fentanyl buccal tablets, paying attention to new indications and methods of use and less known or overlooked aspects that go beyond or extend the well-established knowledge contained in the summary of product characteristics. The possibilities of initiating the treatment with transmucosal fentanyl in proportion to the daily dose of opioids, the dose-proportional effect also in the range exceeding the recommended maximum doses, the safety, and stable dosing during many months of use and the treatment with multiple doses throughout the day are discussed. Off-label applications of research interest, such as prophylactic premedication or treatment of pain exacerbations of a non-cancer etiology, are presented. The favorable safety profile concerning possible abuse by people addicted to psychoactive substances has been discussed in detail. Attention was also drawn to the new ​?application of transmucosal fentanyl in clinical recommendations ? the treatment of episodic dyspnoea.