Since the first proton pump inhibitor (PPI) was approved in 1989, the understanding of this family of drugs has grown. A growing body of evidence indicates the link between the cytochrome P450 2C19 (CYP2C19) phenotype and PPI safety and efficacy. This comprises paediatric studies published in this and other paediatric publications within the last year. Furthermore, according to the most recent paediatric Helicobacter pylori guidelines, utilising PPIs that are less reliant on CYP2C19 for inactivation may be preferable for H pylori eradication in groups that are more prone to have quick clearance of CYP2C19-metabolized PPIs.

In contrast, the package information for pantoprazole suggests a dose reduction in known paediatric CYP2C19 poor metabolizers (PMs), noting a 6-fold rise in serum concentrations as compared to normal metabolizers (NMs). The goal of this communication is to introduce a new Clinical Pharmacogenetics Implementation Consortium (CPIC) guideline for CYP2C19 and PPI dosing.