Date of Award


Document Type

Scholarly Project

Degree Name

Master of Physician Assistant Studies (MPAS)


Physician Assistant Studies

First Advisor

Julie Solberg


CYP2D6: Polymorphisms; Opioid; Metabolism; Pain; Analgesia


The purpose of this research and systematic literature review is to determine if pharmacogenetic testing for the CYP2D6 enzyme responsible for the metabolism of several opiates leads to differences in serum levels, side effects, and treatment outcomes for patients with acute or chronic pain. In this review, the Pubmed and Embase databases were searched from January 1, 2014, to November 1, 2019. Exclusion criteria included studies published before 2014 and those not peerreviewed. For this review, 11 studies were included with designs such as prospective and retrospective cohorts, randomized control trials, systematic reviews, and meta-analyses. Much of the presented research indicates an association between CYP2D6 phenotypes and differential treatment outcomes. Poor CYP2D6 metabolizers are shown to be at increased risk of analgesic failure contrasted with ultra-rapid metabolizers demonstrating better analgesic control; however, they had a higher risk of side effects and toxicity. Conflicting data is also demonstrated as well as a lack of conclusions that can be drawn for more intermediate metabolizers. We know the gene that codes for CYP2D6 is one of many that can affect opiate metabolism. More research is needed that encompasses all of these genes in order to make the findings more applicable to clinical practice.