Administration of strong opioids is a long-established method used to treat chronic pain due to tumours as well as to other non-tumour causes. A physician considering pharmacotherapy makes his decision based on both pharmacological and clinical characteristics of opioids.
Findings from clinical trials and recommendations in relevant guidelines suggest that the drugs of choice are long-acting forms of oral opioids, while it is rational to use transdermal patches in the therapy of patients unable to use oral medications. Relief of breakthrough pain requires special approach and use of opioids with ultra-rapid onset of action.