Esomeprazole magnesium

Esomeprazole Magnesium

Esomeprazole magnesium is a proton pump inhibitor (PPI) used in the treatment of certain stomach and esophagus problems such as acid reflux and gastroesophageal reflux disease (GERD). It works by decreasing the amount of acid the stomach makes, providing relief from symptoms such as heartburn, difficulty swallowing, and persistent cough.

Pharmacology

Mechanism of Action

Esomeprazole magnesium is the S-isomer of omeprazole, which is a racemic mixture. It selectively inhibits the H+/K+ ATPase enzyme system found at the secretory surface of the gastric parietal cell. This enzyme system is also known as the "proton pump" and is responsible for the final step in the production of gastric acid. By inhibiting this enzyme, esomeprazole effectively reduces gastric acid secretion.

Pharmacokinetics

Esomeprazole is acid-labile and is therefore administered as enteric-coated granules or tablets to prevent degradation in the stomach. After oral administration, esomeprazole is rapidly absorbed, with peak plasma levels occurring within 1 to 2 hours. The bioavailability of esomeprazole increases with repeated dosing.

Esomeprazole is extensively metabolized in the liver by the cytochrome P450 system, primarily by CYP2C19 and CYP3A4. The metabolites are inactive and are excreted in the urine and feces.

Clinical Uses

Esomeprazole magnesium is indicated for:

• Treatment of gastroesophageal reflux disease (GERD)
• Healing of erosive esophagitis
• Maintenance of healing of erosive esophagitis
• Risk reduction of NSAID-associated gastric ulcer
• Treatment of pathological hypersecretory conditions, including Zollinger-Ellison syndrome

Adverse Effects

Common side effects of esomeprazole magnesium include:

• Headache
• Diarrhea
• Nausea
• Flatulence
• Abdominal pain

Serious but rare side effects may include:

• Severe allergic reactions
• Clostridium difficile-associated diarrhea
• Bone fractures with long-term use
• Vitamin B12 deficiency with prolonged use

Drug Interactions

Esomeprazole may interact with other medications, including:

• Clopidogrel: Esomeprazole may reduce the effectiveness of clopidogrel by inhibiting CYP2C19, which is necessary for the conversion of clopidogrel to its active form.
• Warfarin: Esomeprazole may increase the risk of bleeding when taken with warfarin.
• Diazepam: Esomeprazole may increase the plasma levels of diazepam.

Dosage and Administration

Esomeprazole magnesium is available in various forms, including delayed-release capsules and oral suspension. The dosage and duration of therapy depend on the condition being treated and the patient's response to therapy.

See Also

• Proton pump inhibitor
• Omeprazole
• Gastroesophageal reflux disease

References

• Prescribing information for esomeprazole magnesium.
• Clinical pharmacology and therapeutic use of esomeprazole.