Comparative Pharmacology
Head-to-head clinical analysis: NEXIUM 24HR versus PRILOSEC OTC.
Peer-Reviewed Evidence
Head-to-head clinical analysis: NEXIUM 24HR versus PRILOSEC OTC.
NEXIUM 24HR vs PRILOSEC OTC
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Esomeprazole is a proton pump inhibitor that suppresses gastric acid secretion by specific inhibition of the H+/K+ ATPase enzyme system at the secretory surface of gastric parietal cells. It is a weak base that accumulates in the acidic environment of the parietal cell canaliculus, where it is protonated and converted to the active achiral sulfenamide form, which forms a covalent disulfide bond with cysteine residues of the H+/K+ ATPase, irreversibly inhibiting the pump.
Proton pump inhibitor that irreversibly inhibits the H+/K+ ATPase enzyme (proton pump) in gastric parietal cells, suppressing gastric acid secretion.
20 mg orally once daily for 14 days for frequent heartburn; for gastroesophageal reflux disease (GERD), 20 mg orally once daily for 4-8 weeks; for erosive esophagitis, 20-40 mg orally once daily 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
The terminal elimination half-life is approximately 1-2 hours in healthy individuals. However, the pharmacodynamic effect (acid suppression) lasts longer due to accumulation in the parietal cell canaliculus and irreversible binding to the proton pump. In poor CYP2C19 metabolizers, half-life may extend to 3-4 hours.
Approximately 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 single oral dose is excreted in urine as metabolites (primarily hydroxy- and desmethyl-omeprazole) and glucuronide conjugates, with less than 1% as unchanged drug. About 19% is eliminated in feces via biliary excretion. Renal clearance accounts for the majority of elimination.
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 C
Category C
Proton Pump Inhibitor
Proton Pump Inhibitor