Although the CPIC® clinical guidelines specifically recommend dose escalation considerations for individuals with the normal, rapid, and ultra-rapid metabolizer CYP2C19 phenotype in the setting of select clinical diagnoses (e.g., H. pylori infection, erosive esophagitis; Table 3), it is the opinion of these authors that these actionable recommendations apply to other conditions for which PPIs have become standard treatment (e.g., GERD, PPI-responsive eosinophilic esophagitis). Here, CYP2C19 is linked to gastroesophageal reflux disease.