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Updated: Jun 30, 2026
07:23
Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
Improved opioid analgesic effect following opioid dose reduction
Yakov Vorobeychik1, Lucy Chen, Mary Chasko Bush
1Department of Anesthesiology, Pain Medicine Division, Penn State Milton S Hershey Medical Center, Penn State College of Medicine, Hershey, Pennsylvania 17033-0850, USA. yvorobeychik@psu.edu
Pain Medicine (Malden, Mass.)
|September 26, 2008
Summary
Opioid-induced hyperalgesia can worsen cancer pain despite increased opioid doses. Reducing opioids and adding an N-methyl-D-aspartate receptor antagonist may improve pain management in refractory cases.
Area of Science:
- Oncology
- Pain Management
- Pharmacology
Background:
- Opioids are standard for cancer pain but can lead to tolerance and opioid-induced hyperalgesia.
- Opioid-induced hyperalgesia is increasingly recognized in chronic pain patients with escalating pain despite dose increases.
Observation:
- A 56-year-old male with recurrent lung cancer and spinal metastases experienced intractable pain (8/10) despite escalating doses of oxycodone, morphine, and hydromorphone.
- The patient exhibited severe pain, sedation, fatigue, and weakness, suggesting opioid-induced hyperalgesia.
- Reducing hydromorphone by 40-50% and initiating methadone decreased pain to 3/10, improving alertness and pain tolerability.
Findings:
- Opioid-induced hyperalgesia should be considered when pain escalates with increasing opioid doses without disease progression.
- A reduction in opioid dosage combined with an N-methyl-D-aspartate receptor antagonist showed a favorable clinical outcome.
Implications:
- This case highlights a potential therapeutic strategy for managing refractory cancer pain.
- Considering opioid-induced hyperalgesia and adjusting opioid therapy may improve patient outcomes and quality of life.
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