Organic brain syndromes and opioid administration for cancer pain

To clarify the range of potential etiologies that may contribute to organic brain syndrome in patients receiving systemic opioids for cancer pain, we describe 15 patients who presented this complication. In 11 cases, concomitant conditions were found that could contribute to the onset of organic brain syndrome. These data illustrate that multiple causes often play a role in the development of mental status changes in advanced cancer. Opioids are seldom the only causal factor implicated.