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Methadone for treatment of cancer pain

John Bryson1, Anoo Tamber, Dori Seccareccia

  • 1Division of Medical Oncology and Hematology, Psychosocial Oncology and Palliative Care Program, Princess Margaret Hospital, Toronto, Ontario, Canada M5G 2M9.

Current Oncology Reports
|January 27, 2007
PubMed

Insights

Methadone, a unique opioid agonist, offers pain relief but requires caution due to its long half-life and potential for delayed toxicity. Further research is needed to evaluate its safety and effectiveness as a first-line pain medication.

Area of Science:

  • Pharmacology
  • Pain Management
  • Clinical Therapeutics

Background:

  • Methadone is a mu opioid agonist with additional N-methyl-D-aspartate receptor antagonist and monoamine reuptake inhibitor properties.
  • It is primarily indicated for uncontrolled pain or opioid dose-limiting toxicities.

Purpose of the Study:

  • To review the unique pharmacological profile of methadone.
  • To highlight clinical considerations for methadone use, including switching from other opioids and potential toxicities.
  • To emphasize the need for further research into methadone's role in pain management.

Main Methods:

  • Literature review of methadone's pharmacological actions and clinical applications.
  • Analysis of safety data, including conversion ratios, half-life, and QT interval prolongation.
  • Identification of research gaps regarding methadone's efficacy and safety.

Main Results:

  • Methadone exhibits complex pharmacology beyond mu opioid agonism.
  • Switching to methadone requires careful consideration due to variable conversion and delayed toxicity risks.
  • Large doses of methadone are associated with QT interval prolongation and torsades de pointes.

Conclusions:

  • Methadone's unique properties necessitate cautious use, especially when transitioning from other opioids.
  • Lower doses of methadone may offer a safer profile, but require further evaluation.
  • Randomized controlled trials are essential to determine methadone's comparative effectiveness and safety in neuropathic pain and as a first-line agent.

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