Pharmacogenetics of Neonatal Opioid Toxicity Following Maternal Use of Codeine During Breastfeeding: A Case-Control Study (original) (raw)

A case-control study evaluated the pharmacogenetics of neonatal opioid toxicity associated with maternal codeine use during breastfeeding. The study revealed that mothers of symptomatic infants had a significantly higher codeine dosage compared to asymptomatic mothers, indicating a potential dose-response relationship. Notably, maternal-infant CNS depression showed strong concordance, particularly in mothers with the CYP2D6 ultrarapid metabolizer phenotype and UGT2B7*2/*2 genotype, who exhibited increased risk of severe neonatal toxicity.