Additional Author Affiliation

New York Medical College

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Publication Title

EC Pharmacology and Toxicology


Use of opioids is essential in providing a broad and effective analgesic effect. Opioid dosing has to be monitored and controlled in order to manage pain and the corresponding side effects due to opioid treatment. A very common single nucleotide polymorphism (SNP) associated with the µ opioid receptor is A118G. A118G, located on exon 1 of the µ-opioid receptor gene (OPRM1), may alter how patients respond to opioid treatment. This polymorphism results in an exchange of adenine for guanine, which in turn leads to substitution of asparagine for the aspartic acid. In order to understand how individuals with the G allele differ from the wild type A118A, it is important to review the response to opioid treatment, as well as to understand the reactions of the opioidergic system to this SNP. Studies show that individuals with the G allele tend to react differently to opioid treatment compared to wild type A118A. Their µ-opioid receptors have decreased sensitivity to opioids, which in turn leads to decreased analgesic effect. People with the G allele may be more predisposed to heroin addiction, drug overdosing, as well as development of breast cancer.

Publisher's Statement

Originally published in EC Pharmacology and Toxicology, 6(4). The original material can be found here.

Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.



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