Comparative Pharmacology
Head-to-head clinical analysis: ACIPHEX versus NEXIUM 24HR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ACIPHEX versus NEXIUM 24HR.
ACIPHEX vs NEXIUM 24HR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Rabeprazole 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.
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.
20 mg orally once daily; duration: 4-8 weeks for erosive esophagitis, 4 weeks for GERD, 24 weeks for H. pylori eradication (triple therapy: AcipHex 20 mg + amoxicillin 1000 mg + clarithromycin 500 mg twice daily for 7 days), 4 weeks for duodenal ulcer, up to 12 months for pathological hypersecretory conditions.
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.
None Documented
None Documented
Plasma half-life 1-2 hours, but pharmacodynamic half-life (acid suppression) >24 hours due to accumulation in parietal cell canaliculi.
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.
Hepatic metabolism, primarily via CYP2C19 and CYP3A4; ~90% eliminated as metabolites in urine, <1% unchanged; remainder in feces.
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.
Category C
Category C
Proton Pump Inhibitor
Proton Pump Inhibitor