Opioid Receptors

Annu Rev Med. 2016:67:433-51. doi: 10.1146/annurev-med-062613-093100. Epub 2015 Aug 26.


Opioids are the oldest and most potent drugs for the treatment of severe pain. Their clinical application is undisputed in acute (e.g., postoperative) and cancer pain, but their long-term use in chronic pain has met increasing scrutiny. This article reviews mechanisms underlying opioid analgesia and other opioid actions. It discusses the structure, function, and plasticity of opioid receptors; the central and peripheral sites of analgesic actions and side effects; endogenous and exogenous opioid receptor ligands; and conventional and novel opioid compounds. Challenging clinical situations, such as the tension between chronic pain and addiction, are also illustrated.

Keywords: addiction; inflammation; pain; peripheral; plasticity; tolerance.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Analgesics, Opioid / pharmacology
  • Analgesics, Opioid / therapeutic use*
  • Chronic Pain / drug therapy
  • Drug Tolerance
  • Humans
  • Ligands
  • Narcotic Antagonists / therapeutic use
  • Neuronal Plasticity
  • Opioid-Related Disorders / etiology
  • Pain / drug therapy*
  • Pain / metabolism
  • Receptors, Opioid / agonists*
  • Receptors, Opioid / drug effects
  • Receptors, Opioid / metabolism*
  • Signal Transduction
  • Time Factors


  • Analgesics, Opioid
  • Ligands
  • Narcotic Antagonists
  • Receptors, Opioid