Pharmacogenetic study of pruritus induced by epidural morphine for post cesarean section analgesia.

OBJECTIVE: The mechanism through which neuroaxial morphine causes pruritus has not been elucidated clearly and thoroughly.

MATERIALS AND METHODS: a study in 129 female parturients was conducted to investigate the effect of 14 single nucleotide polymorphisms (SNPs) on phenotype (pruritus) induced by neuroaxial (including intrathecal or epidural) morphine for cesarean section. Clinical phenotype, subjective complaints and objective observations were recorded. DNA from blood samples was used to record the SNPs. Eleven SNPs were then analyzed further.

RESULTS: no significant association with the presence of phenotype (pruritus) versus genotype was observed (all p-values > 0.05). No significant association with severity of phenotype versus genotype of the 11 SNPs was observed except for unadjusted data for rs2737703. There was no significant difference between severity or incidence of IVPCA morphine-induced nausea and vomiting and genotype (11 SNPs).

CONCLUSION: our results showed no association between SNPs of any of the genes studied with neuroaxial morphine inducing pruritus.