Management of common opioid side effects during long-term therapy of cancer pain.

For most patients with cancer pain, the primary goal of opioid pharmacotherapy is a satisfactory balance between analgesia and side effects. Consequently, the assessment and treatment of opioid side effects is a fundamental aspect of therapy, which may increase the likelihood of a favourable treatment outcome, potentially allow higher and more efficacious opioid doses, and improve quality of life by reducing other uncomfortable symptoms. This review describes the presentation, assessment and management of adverse neuropsychological and gastrointestinal effects due to opioid drugs. These common side effects pose the major challenge for the clinician who undertakes the long-term opioid therapy of patients with cancer pain.