Improved Pain Control in Terminally III Cancer Patients by Introducing Low-Dose Oral Methadone in Addition to Ongoing Opioid Treatment

Background: Cancer pain is often not well controlled and there is a need for improved treatment strategies. Methadone exhibits unique properties among opioids and recent reports show promising results from adding a low dose of methadone to regular opioid therapy. Objective: To examine the effects of oral low-dose methadone added to regular scheduled opioids in terminally ill patients with complex cancer-related pain. Design: This was a retrospective chart review. Setting/Subjects: All patients with advanced cancer treated in a specialized palliative care unit who had received oral methadone in addition to another regular opioid were identified. Measurements: Intensity of pain, opioid doses, and occurrence of sedation, delirium, and respiratory depression were obtained from the patients' medical records for a period of one week after initiation of methadone. Results: Eighty patients were included. The median daily methadone dose was 10 mg during the treatment period. Eighty percent of the patients had improved pain control (p < 0.001). There was an increased risk for sedation and delirium, most pronounced in patients living 14 days or less after the start of methadone. No patient experienced respiratory depression. Conclusion: Addition of low-dose oral methadone to regular high-dose opioid treatment in cancer patients with complex pain close to death improves pain control, but also increases the risk for sedation and delirium.