Comparative Pharmacology
Head-to-head clinical analysis: OMEPRAZOLE versus PRILOSEC OTC.
Peer-Reviewed Evidence
Head-to-head clinical analysis: OMEPRAZOLE versus PRILOSEC OTC.
OMEPRAZOLE vs PRILOSEC OTC
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Proton pump inhibitor that irreversibly inhibits the H+/K+ ATPase enzyme system at the secretory surface of gastric parietal cells, blocking the final step of gastric acid secretion.
Proton pump inhibitor that irreversibly inhibits the H+/K+ ATPase enzyme (proton pump) in gastric parietal cells, suppressing gastric acid secretion.
20-40 mg orally once daily before a meal for 4-8 weeks.
20 mg orally once daily for 14 days for frequent heartburn; may repeat 14-day course every 4 months.
None Documented
None Documented
Terminal elimination half-life is approximately 0.5–1 hour. However, the pharmacodynamic effect (gastric acid suppression) lasts much longer due to irreversible binding to the proton pump. The half-life is prolonged in patients with hepatic impairment (up to 3–4 hours in cirrhosis) and in CYP2C19 poor metabolizers (up to 2–3 hours).
Clinical Note
moderateEsomeprazole + Clodronic acid
"The therapeutic efficacy of Clodronic acid can be decreased when used in combination with Esomeprazole."
Clinical Note
moderateOmeprazole + Clodronic acid
"The therapeutic efficacy of Clodronic acid can be decreased when used in combination with Omeprazole."
Clinical Note
moderateEsomeprazole + Alendronic acid
"The therapeutic efficacy of Alendronic acid can be decreased when used in combination with Esomeprazole."
Clinical Note
moderateApproximately 0.5–1 hour in healthy subjects; longer (up to 3 hours) in slow metabolizers or hepatic impairment. Clinically, the duration of acid suppression exceeds the half-life due to accumulation in parietal cell canaliculi.
Approximately 77% of a dose is excreted in urine (as metabolites, including hydroxyomeprazole and the corresponding carboxylic acid and sulfone derivatives), and about 18% is eliminated in feces via biliary excretion. Less than 1% of the parent drug is excreted unchanged in urine.
Primarily hepatic metabolism; about 80% of metabolites are excreted in urine, and the remainder in feces via bile. Less than 1% of unchanged drug is excreted in urine.
Category A/B
Category C
Proton Pump Inhibitor
Proton Pump Inhibitor
Omeprazole + Alendronic acid
"The therapeutic efficacy of Alendronic acid can be decreased when used in combination with Omeprazole."