Determining the potential clinical value of panel-based pharmacogenetic testing in patients with chronic pain or gastroesophageal reflux disease

We aimed to determine the potential value of panel-based pharmacogenetic (PGx) testing in patients with chronic pain or gastroesophageal reflux disease (GERD) who underwent single-gene PGx testing to guide opioid or proton pump inhibitor (PPI) therapy, respectively. Of 448 patients included (chronic pain, n = 337; GERD, n = 111), mean age was 57 years, 68% were female, and 73% were white. Excluding opiates for the pain cohort and PPIs for the GERD cohort, 76.6% of patients with pain and 71.2% with GERD were prescribed at least one additional medication with a high level of PGx evidence, most commonly ondansetron or selective serotonin reuptake inhibitors. The most common genes that could inform PGx drug prescribing were CYP2C19 , CYP2D6 , CYP2C9 , and SLCO1B1 . Our findings suggest that patients with chronic pain or GERD are commonly prescribed drugs with a high level of evidence for a PGx-guided approach, supporting panel-based testing in these populations.