Analgesic requirements after major abdominal surgery are associated with OPRM1 gene polymorphism genotype and haplotype

Pharmacogenomics. 2008 Nov;9(11):1605-16. doi: 10.2217/14622416.9.11.1605.


Aims: The association between SNPs of the human OPRM1 gene encoding the micro-opioid receptor and postoperative analgesic requirements in surgical patients remains controversial. Here, we evaluate whether any of the five tag SNPs (A118G, IVS2+G691C, IVS3+G5953A, IVS3+A8449G and TAA+A2109G) representing the four linkage disequilibrium blocks of the OPRM1 gene influences postoperative analgesic requirements.

Materials & methods: We studied 138 adult Japanese patients who underwent major open abdominal surgery under combined general and epidural anesthesia and received continuous postoperative epidural analgesia with opioids.

Results: The 118G homozygous (GG) patients required 24-h postoperative analgesics more than 118A homozygous (AA) and heterozygous (AG) patients. Tag SNP haplotypes also were associated with 24-h postoperative analgesic requirements.

Conclusions: These results suggest that OPRM1 gene tag SNP genotypes and haplotypes can primarily contribute to prediction of postoperative analgesic requirements in individual patients undergoing major open abdominal surgery.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abdomen / surgery*
  • Adult
  • Aged
  • Aged, 80 and over
  • Analgesics / administration & dosage
  • Analgesics / therapeutic use*
  • Analgesics, Opioid / administration & dosage
  • Analgesics, Opioid / therapeutic use
  • Anti-Inflammatory Agents, Non-Steroidal / administration & dosage
  • Anti-Inflammatory Agents, Non-Steroidal / therapeutic use
  • Digestive System Surgical Procedures
  • Drug Therapy, Combination
  • Female
  • Genotype
  • Haplotypes
  • Humans
  • Male
  • Middle Aged
  • Pain, Postoperative / genetics
  • Pain, Postoperative / prevention & control*
  • Polymorphism, Single Nucleotide*
  • Receptors, Opioid, mu / genetics*
  • Treatment Outcome


  • Analgesics
  • Analgesics, Opioid
  • Anti-Inflammatory Agents, Non-Steroidal
  • OPRM1 protein, human
  • Receptors, Opioid, mu