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Clinical Pharmacogenetics Implementation Consortium guidelines for cytochrome P450 2D6 genotype and codeine therapy:
K R Crews1, A Gaedigk2, H M Dunnenberger1
1Department of Pharmaceutical Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.
Clinical Pharmacology and Therapeutics
|January 25, 2014
Summary
Codeine
Area of Science:
- Pharmacogenetics
- Drug Metabolism
- Genomics
Background:
- Codeine is converted to morphine by cytochrome P450 2D6 (CYP2D6).
- CYP2D6 activity, influenced by genetic variations (polymorphisms), dictates codeine's effectiveness and safety.
- Understanding CYP2D6 genotype is crucial for optimizing codeine therapy.
Purpose of the Study:
- To update clinical guidelines for codeine therapy based on CYP2D6 genotype.
- To consolidate evidence linking CYP2D6 variability to codeine response.
- To provide actionable therapeutic recommendations for clinicians.
Main Methods:
- Literature review of studies on CYP2D6 genotype and codeine efficacy/safety.
- Analysis of evidence supporting genotype-guided prescribing.
- Development of updated therapeutic recommendations.
Main Results:
- CYP2D6 genetic polymorphisms significantly impact codeine bioactivation to morphine.
- Specific genotypes are associated with poor, intermediate, or rapid/ultra-rapid metabolism.
- These metabolic differences correlate with varying levels of analgesia and adverse events.
Conclusions:
- Genotype-guided prescribing of codeine is essential for maximizing efficacy and minimizing risks.
- Updated Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines provide a framework for implementation.
- Personalized medicine approaches using pharmacogenetics improve patient outcomes with codeine.
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