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Updated: May 8, 2026

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
[Opioid insensitivity associated with genetic variants in the μ-opioid receptor]
Anton Lund1, Malene Djursby2, Pia Jæger1
1Afdeling for Bedøvelse og Operation i Juliane Marie Centret, Københavns Universitetshospital - Rigshospitalet.
Abstract:
Interindividual variation in opioid response is well described, but complete insensitivity is exceedingly rare. In this case report, a healthy 32-year-old female demonstrated no clinical effect of large doses of opioids. Exome sequencing revealed two variants in the OPRM1 encoding the μ-opioid receptor, offering a plausible genetic explanation. The patient was anaesthetised for two laparoscopic procedures, and successful management relied on a multimodal strategy including esketamine and epidural analgesia.
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