Proton Pump Inhibitors (PPIs)

CYP2C19 Pharmacogenomic Panel

Why Genotyping Matters

Metabolic Variability

PPIs are cleared mainly by CYP2C19; genotype can alter drug exposure >20-fold between ultra-rapid and poor metabolizers.

Therapeutic Impact

H. pylori eradication and erosive-esophagitis healing rates fall to ≤ 60% in rapid/ultra-rapid metabolizers (RM/UM) at standard doses, but exceed 90% in poor metabolizers (PM).

Guideline Consensus

The 2020 CPIC guideline provides explicit dose or drug-selection changes for every CYP2C19 phenotype; recommendations are graded strong or moderate.

Allele Prevalence

Population*2 (LOF)*3 (LOF)*17 (GOF)% IM + PM% RM + UM
East Asian29 – 35 %6 – 10 %≈ 3 %~45 %~4 %
European15 %< 1 %20 – 25 %~18 %~35 %
African-American15 %< 1 %16 %~18 %~30 %

Who Should Be Tested?

Patients starting long-term PPI therapy (GERD, Barrett’s, chronic NSAID prophylaxis)

Prevent sub- or supra-therapeutic exposure

H. pylori eradication or erosive esophagitis requiring maximal acid suppression

Higher cure rates when dose tailored

Refractory heartburn or PPI failure at standard dose

RM/UM most likely

Infants/children needing prolonged PPI (e.g., eosinophilic esophagitis)

Evidence of phenotype-driven dose differences

Individuals with East-Asian ancestry (high LOF allele rate)

Nearly half are IM/PM

Your Journey with Genolife Services

A clear path to optimizing Irinotecan therapy.

Pre-test Counselling

Understand benefits, limitations, inheritance, and therapy options.

Sample Collection

3 mL EDTA blood.

Expert Interpretation

Clinical Geneticist, Genetic Counsellor, Pharmacogenomic Pharmacologist, and Gastroenterologist review.

Actionable Report & Dose Planning

Ready to plan for a safer health future?

Book a Consultation

References

  • Lima JJ et al. CPIC Guideline for CYP2C19 and Proton Pump Inhibitor Dosing. Clin Pharmacol Ther. 2020.
  • CPIC Supplement Tables (Phenotype & Dosing). 2020.
  • Ionova Y et al. CYP2C19 *2/ 3/17 allele frequencies in 2.2 million individuals. Clin Transl Sci. 2020.
  • Scott SA. CYP2C19*17 pharmacogene review. Pharmacogenomics J. 2012.
  • CPIC Guideline PDF – exposure, efficacy & adverse effects discussion.

Hi there!

Getting in touch with us has never been easier.

Subscribe Newsletter

From Bangkok Hospital Phuket

กรุณากรอกอีเมลคุณเพื่อรับข่าวสารจากโรงพยาบาล