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Apnea in a child after oral codeine: a genetic variant - an ultra-rapid metabolizer

Polina Voronov1, Henry J Przybylo, Narasimhan Jagannathan

  • 1Department of Anesthesiology, Children's Memorial Hospital, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA. pvoronov@childrensmemorial.org

Paediatric Anaesthesia
|June 15, 2007
PubMed

Insights

A child experienced apnea and brain injury after acetaminophen and codeine due to ultra-rapid codeine metabolism from a CYP2D6 gene variation. This highlights risks of codeine in specific genetic profiles.

Area of Science:

  • Pharmacogenomics
  • Pediatric Anesthesiology
  • Neuroscience

Background:

  • Codeine is commonly prescribed for pain management in children.
  • Genetic variations, particularly in the CYP2D6 gene, can significantly alter drug metabolism.
  • Acetaminophen and codeine combination is frequently used post-tonsillectomy.

Observation:

  • A 29-month-old child developed apnea and subsequent brain injury after receiving acetaminophen and codeine.
  • The adverse event occurred two days post-anesthesia for tonsillectomy.
  • The child was previously healthy with no prior medical conditions.

Findings:

  • The child possessed a genetic polymorphism resulting in ultra-rapid metabolism of codeine to morphine.
  • This rapid conversion led to toxic levels of morphine, causing central nervous system depression, narcosis, and apnea.
  • The specific CYP2D6 genotype explained the severe adverse drug reaction.

Implications:

  • This case underscores the critical importance of pharmacogenetic screening for codeine prescribing, especially in pediatric populations.
  • Understanding CYP2D6 variations is crucial for preventing adverse drug events and ensuring patient safety.
  • Guidelines for codeine use in children may need revision to incorporate genetic testing for ultra-rapid metabolizers.

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