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Updated: May 31, 2026
14:56
An Experimental Paradigm for the Prediction of Post-Operative Pain (PPOP)
Published on: January 27, 2010
CYP2D6 polymorphisms and codeine analgesia in postpartum pain management: a pilot study
Sondra VanderVaart1, Howard Berger, Johanna Sistonen
1Department of Pharmaceutical Sciences, University of Toronto, Ontario, Canada.
Therapeutic Drug Monitoring
|July 12, 2011
Summary
Codeine
Area of Science:
- Pharmacogenomics
- Pain Management
- Postoperative Care
Background:
- Codeine is a common analgesic after cesarean section (c-section).
- Codeine metabolism varies significantly due to Cytochrome P450 enzyme 2D6 (CYP2D6) genetic variations.
- CYP2D6 ultrarapid metabolizers (UMs) convert more codeine to morphine, while poor metabolizers (PMs) convert very little.
Purpose of the Study:
- To investigate the association between CYP2D6 genotype and codeine's effectiveness for pain relief in women after c-section.
- To explore how genetic variations in CYP2D6 influence pain scores and the need for analgesia.
Main Methods:
- Collected blood samples for CYP2D6 genotyping from 45 mothers post-c-section.
- Monitored pain levels, codeine usage, and adverse events for three days.
- Estimated theoretical morphine dosage based on individual CYP2D6 genotype.
Main Results:
- Poor metabolizers (PMs) reported no pain relief from codeine.
- Ultrarapid metabolizers (UMs) experienced rapid pain relief but reported side effects like dizziness and constipation.
- Further research with larger cohorts is needed for intermediate metabolizer genotypes.
Conclusions:
- Extreme CYP2D6 genotypes (PMs and UMs) appear to predict codeine response and adverse events post-c-section.
- This pilot study highlights the potential of pharmacogenomics in tailoring postoperative pain management.
- Larger studies are required to establish genotype-phenotype correlations across the full spectrum of CYP2D6 metabolizers.
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