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Updated: Mar 30, 2026

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Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
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Opioid-Induced Hyperalgesia: A Diagnostic Dilemma
Journal of Pain & Palliative Care Pharmacotherapy
|November 3, 2015
Summary
Opioid therapy for chronic pain can lead to opioid-induced hyperalgesia (OIH), a state of increased pain sensitivity. Recognizing OIH is crucial for effective pain management and may necessitate opioid rotation, such as to methadone.
Area of Science:
- Pain Management
- Pharmacology
- Oncology
Background:
- Opioids are commonly prescribed for moderate to severe acute and cancer-related pain.
- Chronic opioid therapy requires awareness of tolerance, withdrawal, and opioid-induced hyperalgesia (OIH).
Observation:
- Escalating opioid therapy requires understanding the difference between tolerance and OIH.
- A case study highlights high-dose opioid therapy failing to manage chronic pain and inducing hyperalgesia.
Findings:
- Opioid-induced hyperalgesia (OIH) can exacerbate pain despite aggressive pharmacologic measures.
- Opioid rotation to methadone may be advantageous when OIH is suspected.
Implications:
- Judicious opioid utilization is essential in cancer pain management.
- Differentiating OIH from tolerance is key for optimizing analgesic titration.
- Methadone may offer benefits in managing OIH during chronic opioid therapy.
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