Complicated Pain Management in a CYP450 2D6 Poor Metabolizer

@article{Foster2007ComplicatedPM,
  title={Complicated Pain Management in a CYP450 2D6 Poor Metabolizer},
  author={Adriana Foster and Elizabeth Mobley and Zixuan Wang},
  journal={Pain Practice},
  year={2007},
  volume={7}
}
▪ Abstract:  We describe the case of a patient with significant adverse effects from posttraumatic analgesic therapy with opioid analgesics who was found by microarray analysis to have a CYP2D6 genotype predictive of a poor metabolizer phenotype. In addition to her poor tolerance and limited response to opioid analgesics, she developed further discomfort when the antiemetic promethazine was administered to treat her gastrointestinal adverse effects. In our discussion we review the literature… 
IN RESPONSE TO DR. AHDIEH
TLDR
It is proposed that another option for those patients who are poor CYP2D6 metabolizers might be oxymorphone, which does not undergo any form of CYP450 metabolism but is instead metabolized primarily via glucuronidation, which might reduce the potential complications associated with opioid therapy in CYP1D6 poor metabolizers, and might also have a lower interaction potential when administered concurrently with other CYP 450-dependent drugs.
REGARDING CYP450 2D6 POOR METABOLIZERS
  • H. Ahdieh
  • Medicine, Biology
    Pain practice : the official journal of World Institute of Pain
  • 2008
TLDR
It is proposed that another option for those patients who are poor CYP2D6 metabolizers might be oxymorphone, which does not undergo any form of CYP450 metabolism but is instead metabolized primarily via glucuronidation, which might reduce the potential complications associated with opioid therapy in CYP1D6 poor metabolizers, and might also have a lower interaction potential when administered concurrently with other CYP 450-dependent drugs.
The value of CYP2D6 and OPRM1 pharmacogenetic testing for opioid therapy.
Towards personalized opioid dosing: A concise overview of CYP polymorphisms
TLDR
Patients who have genotype polymorphisms in these enzymes are phenotypically (clinically) poor, intermediate, extensive, or ultra-rapid metabolizers, affecting how rapidly or to what extent an individual patient metabolizes opioids.
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TLDR
YP2D6 genotypes did not influence pain control, the adverse symptoms nausea and sedation or the risk for cognitive failure in patients treated with oxycodone for cancer pain, and had no pharmacodynamic consequence.
Identification of Cytochrome P450 Polymorphisms in Burn Patients and Impact on Fentanyl Pharmacokinetics: A Pilot Study.
TLDR
This pilot study supports the need for further research in this topic, and CYP genotyping of individual patients prior to receiving opiate analgesics to inform precision-guided decisions, improve therapeutic efficacy, and, most importantly, increase patient well-being and safety.
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TLDR
There is no clear evidence that genetic markers can be used to predict opioid efficacy or adverse effects in palliative care patients, which reflects the general lack of studies performed in the context of palliatives care, the lack of sufficiently scaled studies and the Lack of international standards for the assessment of subjective symptoms.
A review of the role of genetic testing in pain medicine.
TLDR
Genetic testing may explain and predict many of the clinical responses seen with opioids and adjuvant medications, and may help the clinician identify those patients at genetic risk of opioid misuse and addiction.
Contribution of CYP2D6 Functional Activity to Oxycodone Efficacy in Pain Management: Genetic Polymorphisms, Phenoconversion, and Tissue-Selective Metabolism
TLDR
It is opine that pharmacogenetic testing, especially for CYP2D6 with considerations of phenoconversion due to concomitant drug administration, should be appraised to improve oxycodone efficacy.
The pharmacogenomics of pain management: prospects for personalized medicine
TLDR
This narrative review will attempt to cover the current understanding of the pharmacogenomics of pain, examining common genes affecting metabolism of analgesic medications, their distribution throughout the body, and end organ effects.
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