Clinical use of opioids for cancer pain.

Successful management of pain in the cancer patient requires careful assessment of the components of the pain complaint and accurate diagnosis of the cause of pain. Symptomatic management of pain involves pharmacotherapeutic strategies that focus on opioid use. Factors influencing the choice of opioid in patients with cancer pain include the severity of pain, the presence of coexisting disease, response to previous analgesic therapy, pharmacokinetic factors, available formulations, and patient compliance. Long-term opioid prescription always requires individual titration of medication to adequate pain relief, which is determined on an individual patient basis and/or based on manageable adverse effects. Failure to continuously monitor opioid use generally results in overtreatment or undertreatment of pain. The cognitive and psychomotor effects of long-term opioid therapy are not well-defined and merit further study.