Proton Pump Inhibitors: PPI Review for the PTCE Exam

What Are Proton Pump Inhibitors?

Proton pump inhibitors (PPIs) are among the most widely prescribed drug classes in the United States. They work by irreversibly blocking the hydrogen-potassium ATPase enzyme system (the proton pump) in the gastric parietal cells, effectively shutting down acid production. They are used for GERD, peptic ulcers, H. pylori eradication (as part of combination therapy), and Zollinger-Ellison syndrome.

Common PPIs (Generic / Brand)

Omeprazole (Prilosec) - Available OTC and prescription; most commonly prescribed PPI
Esomeprazole (Nexium) - S-enantiomer of omeprazole; available OTC
Pantoprazole (Protonix) - Available IV for hospital use
Lansoprazole (Prevacid) - Available as orally disintegrating tablet
Rabeprazole (Aciphex)
Dexlansoprazole (Dexilant) - Dual delayed-release formulation

Counseling Points

PPIs should be taken 30-60 minutes before the first meal of the day for optimal effectiveness. Delayed-release capsules should be swallowed whole, not crushed or chewed. For patients who cannot swallow capsules, some PPIs can be opened and sprinkled on applesauce (check specific product labeling).

Side Effects and Long-Term Risks

Short-term: headache, nausea, diarrhea, abdominal pain
Long-term use concerns: increased risk of C. difficile infection, bone fractures (hip, wrist, spine), hypomagnesemia, vitamin B12 deficiency, kidney disease
FDA recommends using the lowest effective dose for the shortest duration

Drug Interactions

Omeprazole inhibits CYP2C19, which can affect clopidogrel activation (potentially reducing its antiplatelet effect). This interaction has led many providers to switch to pantoprazole when a PPI is needed with clopidogrel. PPIs also reduce absorption of drugs that require an acidic environment, including ketoconazole, iron supplements, and certain HIV medications.

PPIs are high-yield for the PTCE medications domain. Know the brand-generic pairs and key interactions.