CNS Drugs

, Volume 28, Issue 4, pp 319–329 | Cite as

The Mu-Opioid Receptor Agonist/Noradrenaline Reuptake Inhibition (MOR–NRI) Concept in Analgesia: The Case of Tapentadol

  • Thomas M. TzschentkeEmail author
  • Thomas Christoph
  • Babette Y. Kögel
Review Article


Tapentadol is a novel, centrally-acting analgesic drug, with an analgesic efficacy comparable to that of strong opioids such as oxycodone and morphine. Its high efficacy has been demonstrated in a range of animal models of acute and chronic, nociceptive, inflammatory, and neuropathic pain as well as in clinical studies with moderate to severe pain arising from a number of different etiologies. At the same time, a favorable gastrointestinal tolerability has been demonstrated in rodents and humans, and advantages over morphine regarding tolerance development and physical dependence were shown in animal studies. Furthermore, a low level of abuse and diversion is beginning to emerge from first post-marketing data. Tapentadol acts as a μ-opioid receptor (MOR) agonist and noradrenaline reuptake inhibitor (NRI). Both mechanisms of action have been shown to contribute to the analgesic activity of tapentadol and to produce analgesia in a synergistic manner, such that relatively moderate activity at the two target sites (MOR and noradrenaline reuptake transporter) is sufficient to produce strong analgesic effects. It has been suggested that tapentadol is the first representative of a proposed new class of analgesics, MOR–NRI. This review presents the evidence that has led to this suggestion, and outlines how the pharmacology of tapentadol can explain its broad analgesic activity profile and high analgesic potency as well as its favorable tolerability.


Morphine Tramadol Antinociceptive Effect Chronic Constriction Injury Tapentadol 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Written and funded by Grünenthal GmbH.

Conflict of interest

The authors are employees of Grünenthal GmbH, the inventor and manufacturer of tapentadol.


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Thomas M. Tzschentke
    • 1
    Email author
  • Thomas Christoph
    • 1
  • Babette Y. Kögel
    • 1
  1. 1.Grünenthal GmbH, Grünenthal Innovation, Global Preclinical Research and DevelopmentAachenGermany

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