Za Pharmacy
Drugs, Supplies and Delivery
Esomeprazole (Nexium)
Esomeprazole, marketed under the brand name Nexium, is a proton pump inhibitor (PPI) widely used to reduce gastric acid secretion. It is the S-isomer of omeprazole and offers improved efficacy and pharmacokinetics. Esomeprazole is effective in treating conditions such as gastroesophageal reflux disease (GERD), peptic ulcers, and Zollinger-Ellison syndrome. This article synthesizes information from the British National Formulary (BNF), Lippincott Textbook of Pharmacology, and Lange Basic & Clinical Pharmacology to provide a detailed overview of esomeprazole, including its mechanism, uses, dosing, side effects, precautions, and drug interactions.
Esomeprazole is a prodrug that is activated in the acidic environment of the stomach. It irreversibly inhibits the H+/K+-ATPase (proton pump) on the secretory surface of gastric parietal cells. By blocking this enzyme, esomeprazole:
- Reduces basal and stimulated gastric acid secretion, including acid secretion induced by food, histamine, and gastrin.
- Increases gastric pH, promoting healing of acid-related damage and providing symptomatic relief (Lippincott, Lange).
Esomeprazole’s effects last up to 24 hours, making it suitable for once-daily dosing (BNF).
- Gastroesophageal Reflux Disease (GERD):
- Provides symptomatic relief and promotes healing of esophagitis (BNF).
- Peptic Ulcer Disease:
- Used for the treatment and prevention of gastric and duodenal ulcers (Lippincott).
- Zollinger-Ellison Syndrome:
- Manages excessive gastric acid secretion in this rare condition (Lange).
- Helicobacter pylori Eradication:
- Used in combination with antibiotics (e.g., clarithromycin, amoxicillin) to eradicate H. pylori and prevent ulcer recurrence (BNF).
- Stress Ulcer Prophylaxis:
- Used in critically ill patients to prevent stress-related mucosal damage (Lippincott).
- GERD:
- Treatment: 20–40 mg once daily for 4–8 weeks.
- Maintenance: 20 mg once daily (BNF).
- Peptic Ulcer Disease:
- 20–40 mg once daily for 4–8 weeks (Lippincott).
- Zollinger-Ellison Syndrome:
- Initial dose: 40 mg twice daily, adjusted based on acid secretion levels (Lange).
- H. pylori Eradication:
- 20 mg twice daily in combination with antibiotics for 7–14 days (BNF).
- Stress Ulcer Prophylaxis:
- 20–40 mg once daily (Lippincott).
Administration:
- Take 30–60 minutes before meals for optimal absorption.
- Capsules should be swallowed whole; do not crush or chew (Lange).
- Common: Headache, nausea, diarrhea, and abdominal pain (Lippincott).
- Serious:
- Hypomagnesemia: Prolonged use may lead to low magnesium levels.
- Increased Risk of Infections: Higher risk of Clostridioides difficile and pneumonia.
- Bone Fractures: Long-term use may increase the risk of osteoporosis-related fractures (BNF).
- Hypomagnesemia: Monitor magnesium levels in patients on long-term therapy (Lippincott).
- Vitamin B12 Deficiency: Prolonged use may reduce vitamin B12 absorption; monitor levels in at-risk patients (Lange).
- Pregnancy: Use only if benefits outweigh risks; limited data available (BNF).
- Liver Impairment: Dose reduction may be necessary in patients with severe hepatic impairment (Lippincott).
- Clopidogrel: Esomeprazole may reduce the antiplatelet effects of clopidogrel by inhibiting CYP2C19 (BNF).
- Warfarin: Increased risk of bleeding due to altered metabolism (Lippincott).
- Diazepam and Phenytoin: Esomeprazole may increase levels of these drugs by inhibiting CYP2C19 (Lange).
- Methotrexate: Esomeprazole may increase methotrexate levels, raising the risk of toxicity (BNF).
Esomeprazole is the generic name for this medication. It is marketed under the brand name Nexium®. Generic versions are widely available and cost-effective.
