Last reviewed 2026-04-20 · How we verify

Nexium (esomeprazole)

Esomeprazole (Nexium) is the S-enantiomer of omeprazole, developed by AstraZeneca and approved in 2001. Once a top-10 global drug by revenue, it is now available OTC and generically.

At a glance

Approved indications

• Frequent Heartburn

Common side effects

• Headache
• Diarrhea
• Nausea
• Flatulence
• Abdominal pain
• Constipation
• Dry mouth

Serious adverse events

• GI hemorrhage
• Angioedema
• Anaphylactic reaction
• Hepatic function abnormal
• Thrombocytopenia
• Leukopenia
• Larynx edema
• Dysphagia
• Melena
• Vomiting

Key clinical trials

• An Open-Label, Parallel-Group, Multi-Centre Study to Determine the Effect of Treatment With Esomeprazole for Six Months on Histological Markers of Esophageal Epithelial Acid-Related Disease in Patient (Phase 3)
• Clinical Study on Bifidobacterium Quadruple Live Bacteria Tablets (Si Lian Kang) Reducing the Incidence Rate of Adverse Reactions in Helicobacter Pylori Quadruple Eradication Therapy and on the Effect (Phase 4)
• A Phase II Study to Investigate the Safety and Efficacy of Dexloxiglumide for the Relief of Symptoms of Functional Dyspepsia. (Phase 2)
• Efficacies of Two Bismuth Quadruple Therapies in the Second-line Treatment of H Pylori Infection - a Multi-center Randomized Controlled Trial (NA)
• The Therapeutic Role of Albumin Supply on Peptic Ulcer Bleeding and the Correlation Between Clinical Course and Expression of Serum Response Factor on Ulcer Tissue and Superoxide Free Radical in Blood (Phase 4)
• The Rates of Complete Symptom Relief,Prevetion of Symptom Relapse and Maintenance of Esophagitis Healing for 4-week Versus 8-week Esomeprazole Therapy Among Los Angeles Grades A and B Erosive Esophagi (Phase 4)
• A Multicenter, Randomized, Open-label Phase IV Study Exploring Symptom Control Rate in Co-diagnosed NERD and Chronic Gastritis Patients Treated With 8 Weeks Esomeprazole Treatment Regimen and 2 Weeks (Phase 4)
• A Randomized, Double-blind, Double-dummy, Active Comparator, Multi-centers, Non-inferiority Design Clinical Trial to Assess the Efficacy and Safety of YYD601 in the Treatment of Esophageal Reflux Dise (Phase 3)

Primary sources

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