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Opioid-induced hyperalgesia and tolerance: understanding opioid side effects
Jay S Grider1, William E Ackerman
1Assistant Professor, University of Kentucky, College of Medicine, Department of Anesthesiology, 800 Rose Street Suite, N 201, Lexington, KY 40536, USA. jsgrid2@email.uky.edu ; www.mc.uky.edu/anesthesiology.
Expert Review of Clinical Pharmacology
|January 16, 2014
Summary
Opioid therapy may worsen pain through opioid-induced hyperalgesia, not just tolerance. Reducing opioid dosage, not increasing it, may relieve pain and prevent this effect.
Area of Science:
- Neuroscience
- Pharmacology
- Pain Management
Background:
- Opioid therapy failure in chronic pain management can indicate opioid-induced pain or tolerance.
- Increased opioid dosage may not resolve ineffective pain management and can exacerbate pain.
Purpose of the Study:
- To explore the relationship between opioid therapy, pain, and tolerance.
- To investigate the underlying mechanisms of opioid-induced hyperalgesia and tolerance.
Main Methods:
- Review of current scientific evidence and proposed mechanisms.
- Analysis of the interplay between opioid receptors and NMDA receptors.
Main Results:
- Opioid-induced pain and tolerance may share common underlying mechanisms.
- N-methyl-D-aspartate (NMDA) receptor modulation of opioid receptor-based hyperalgesia is increasingly evident.
- Decreasing opioid dosage can alleviate pain in some cases.
Conclusions:
- Opioid-induced hyperalgesia is a critical consideration in pain management.
- Interrupting cellular changes during opioid tolerance may prevent opioid-induced pain.
- Future research could enable personalized pharmacologic pain therapy for susceptible patients.
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