Opioid use in cancer pain. Is a more liberal approach enhancing toxicity?

The majority of cancer patients develop pain before death. This pain has been shown to be underdiagnosed and undertreated. Opioid use has increased in the past 20 years in both developing and developed countries. The changing pattern in opioid use has resulted in the emergence of neurotoxicity as a major side effect of the treatment of cancer pain. The syndrome of opioid- induced neurotoxicity (OIN) encompasses delirium, hallucinosis, myoclonus/seizures and hyperalgesia. Increased vigilance can lead to the timely diagnosis of OIN, and strategies for its treatment can be implemented with encouraging results. Identification and modification of risk factors for the development of OIN can help in its prevention and improve the quality of life in advanced cancer patients.