Opioids for the management of breakthrough pain in cancer patients.

This review is an update of a previously published review in the Cochrane Database of Systematic Reviews (Issue 1, 2006). Breakthrough pain is a transient exacerbation of pain that occurs either spontaneously or in relation to a specific predictable or unpredictable trigger despite relative stable and adequately controlled background pain. Breakthrough pain usually related to background pain and is typically of rapid onset, severe in intensity and generally self limiting with a mean duration of 30 minutes. Breakthrough pain has traditionally been managed by the administration of supplemental oral analgesia (rescue medication) at a dose proportional to the total around-the-clock (ATC) opioid dose.