Abstract
Breakthrough pain (BP) occurs in patients with chronic tumour-related pain. It is characterised by rapidly increasing intensity of baseline pain and spontaneous resolution, mostly within 30 minutes of its onset.
Drugs used to treat BP must therefore exhibit sufficiently rapid onset of action and limited duration of action at the same time. These requirements are not met by oral opioid forms, but recently transmucosal drug forms have become available, including transmucosal fentanyl citrate that is now available as buccal, sublingual or intranasal drug forms.
Fentanyl in the form of nasal spray demonstrates rapid absorption, and therefore rapid onset of action. Its efficacy, safety, and tolerance have been shown in several clinical studies comparing the drug not only to placebo but also to active treatment.
Clinical studies have also found that lower fentanyl doses were associated with analgesia when intranasal administration was used compared to buccal application. Fentanyl nasal spray is thus a very welcome means to use in the therapy of BP.