1. Abstral^® Fachinformation, August 2024.

2. Portenoy RK. et al., Breakthrough pain: characteristics and impact in patients with cancer pain, Pain. 1999;81:129–134.

3. Portenoy RK. And Hagen NA., Breakthrough pain: definition, prevalence and characteristics, Pain. 1990;4:273–281.

4. Simmonds MA., Management of Breakthrough Pain Due to Cancer Oncology. 1999;13(8):1–9.

5. Fallon M. et al., Management of cancer pain in adult patients: ESMO Clinical Practice Guidelines, Annals of Oncology 2018, 29(Supplement 4): iv166–iv191.

6. Mercadante M et al., Breakthrough cancer pain: twenty-five years of study, Pain. 2016;157(12):2657–2663.

7. Rauck RL et al., Efficacy and long-term tolerability of sublingual fentanyl orally disintegrating tablet in the treatment of breakthrough cancer pain, Curr Med Res Opin. 2009;25(12):2877–2885.

8. Überall MA. et al. , Efficacy and long-term tolerability of sublingual fentanyl orally disintegrating tablet in the treatment of breakthrough cancer pain, Curr Med Res Opin. 2011;27(7):1385–1394.