Wikipedia
Abstral is a formulation of fentanyl citrate available as a sublingual tablet. It dissolves quickly and is absorbed through the sublingual mucosa to provide rapid analgesia. In the UK, Abstral is licensed for the treatment of breakthrough cancer pain (BTcP) in patients with otherwise stable, baseline persistent pain that is managed with conventional opioids.
The active constituent of Abstral is fentanyl, which is classified as a controlled Class A drug under the Misuse of Drugs Act 1971 in the UK.
When used under license, fentanyl is a highly lipophilic compound, which is well absorbed sublingually and generally well tolerated. Other pharmaceutical preparations licensed for breakthrough cancer pain in the UK, which contain fentanyl are: Actiq, Effentora, Instanyl and PecFent. Abstral is manufactured and marketed by Sentynl Therapeutics, Inc..
Currently, patients receive conventional oral opioids (e.g. morphine) to treat their breakthrough cancer pain episodes. However, the pharmacokinetic profile of conventional opioids does not fit the profile of breakthrough cancer pain. A breakthrough cancer pain episode is rapid in onset, short in duration and severe in intensity, while an opioid such as morphine is slow in onset and long in duration. This necessitated the development of specialised, fast-acting fentanyl preparations.