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Updated: Jan 27, 2026

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
The relationship between antemortem and postmortem morphine concentrations
Nigel J Langford1, Stephen R Morley2, Robin E Ferner3
1University Hospital of Leicester, University of Leicester, Leicester, United Kingdom of Great Britain and Northern Ireland.
Abstract:
Context of the Article: An important forensic problem is whether the presence of a drug such as morphine caused or contributed to a death or was merely incidental. The reliance that can be based on postmortem drug concentrations remains controversial. To investigate this further we obtained antemortem and postmortem samples of individuals admitted to hospital who were receiving morphine and who died in hospital.Methods: Eleven subjects were recruited. Samples were sent for analysis for free and total morphine concentrations.Results: The median difference (postmortem - antemortem) free morphine concentration was 25.5 (range 0 to +126) µg/L, p < .01; the mean difference between postmortem and antemortem total morphine concentration was 34.5 (range -225 to 342) µg/L (not significant).Discussion: Our study supports previous investigators who note that there is an inconstant and sometimes tenuous relationship between ante- and postmortem morphine concentrations.
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