Last reviewed 2026-04-20 · How we verify

omeprazole, 20mg twice daily

omeprazole, 20mg twice daily is a Proton Pump Inhibitor (PPI) Small molecule drug developed by Tel-Aviv Sourasky Medical Center. It is currently FDA-approved. Also known as: PPI Platelet Inhibitory.

Omeprazole reduces stomach acid production by irreversibly inhibiting the H+/K+ ATPase enzyme in gastric parietal cells.

Omeprazole is a proton pump inhibitor (PPI) used to reduce stomach acid production. It is prescribed for conditions such as gastroesophageal reflux disease (GERD), peptic ulcer disease, and Zollinger-Ellison syndrome. The drug works by inhibiting the H+/K+ ATPase enzyme system in the gastric parietal cells, effectively reducing acid secretion. Despite its efficacy, omeprazole has several side effects, including headache, diarrhea, and nausea. The drug is not associated with any boxed warnings but has specific contraindications and interactions that should be considered. Omeprazole is widely used and has been on the market for many years, with significant competition from other PPIs.

At a glance

Mechanism of action

Omeprazole is a prodrug that is activated in the acidic environment of the stomach, where it forms a sulfenamide derivative that binds to the H+/K+ ATPase enzyme, inhibiting the final step of acid production.

Approved indications

Common side effects

• Headache
• Diarrhea
• Nausea
• Abdominal pain
• Vomiting
• Dizziness
• Constipation

Drug interactions

• Warfarin: Increased INR and risk of bleeding
• Phenytoin: Increased serum levels of phenytoin
• Clopidogrel: Reduced effectiveness of clopidogrel
• Mycophenolate mofetil: Decreased mycophenolic acid exposure

Key clinical trials

• Esomeprazole Plus Sucralfate for Post-ESD Ulcer Healing (PHASE4)
• Fatty Acid Synthase Inhibition in Castration Refractory Prostate Cancer (PHASE2)
• OPEN Versus InTact Capsule Proton Pump Inhibitors for the Treatment of Marginal Ulcers (PHASE4)
• Vonoprazan vs Proton Pump Inhibitor With Vitamin D or Probiotics Based Triple Therapy for Eradication of Helicobacter Pylori Infection (PHASE2)
• Study of IDE196 in Patients With Solid Tumors Harboring GNAQ/11 Mutations or PRKC Fusions (PHASE1, PHASE2)
• Tegoprazan-Amoxicillin Dual Therapy vs. Bismuth Quadruple Therapy for H. Pylori Infection (TATH-1) (PHASE4)
• Comparative Effectiveness of Triple Versus Quadruple Therapy in the Treatment of Helicobacter Pylori Induced Gastritis (PHASE4)
• Comparative Study Evaluating Safety and Effectiveness of ( Proton Pump Inhibitor Versus Vonoprazan ) Based Triple Therapy With or Without Zinc to Eradicate H. Pylori Infection (PHASE3)

Patents

Primary sources

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Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• omeprazole, 20mg twice daily CI brief — competitive landscape report
• omeprazole, 20mg twice daily updates RSS · CI watch RSS
• Tel-Aviv Sourasky Medical Center portfolio CI

Frequently asked questions about omeprazole, 20mg twice daily

Related

• Drug class: All Proton Pump Inhibitor (PPI) drugs
• Target: All drugs targeting H+/K+ ATPase enzyme
• Manufacturer: Tel-Aviv Sourasky Medical Center — full pipeline
• Therapeutic area: All drugs in Metabolic
• Also known as: PPI Platelet Inhibitory
• Compare: omeprazole, 20mg twice daily vs similar drugs
• Pricing: omeprazole, 20mg twice daily cost, discount & access