Esomeprazole

Products

Esomeprazole is commercially available as tablets, film-coated tablets, granules for oral suspension, and injectables (Nexium, generics). It has been approved in many countries since 2000. Generics entered the market in 2012. Fixed combinations:

Structure and properties

Esomeprazole (C17H19N3O3S, Mr = 345.4 g/mol) is the -enantiomer of omeprazole and is present in the drug, for example, as magnesium esomeprazole trihydrate, a white powder that is sparingly soluble in water. In generics, it is also present as a dihydrate.

Effects

Esomeprazole (ATC A02BC05) reduces secretion of stomach acid by inhibiting the proton pump (H+/K+-ATPase) in the gastric vestibular cells irreversibly. It does not act locally in the lumen of the stomach but is absorbed in the intestine and travels to the vestibular cells via the systemic circulation. It is a prodrug and is converted from acid to its active form only in the canaliculi of the vestibular cells, where it binds covalently to the proton pump, inhibiting it. Esomeprazole is acid labile and must be administered in enteric-coated dosage forms. Esomeprazole has a higher bioavailability than –omeprazole because it is metabolized to a lesser extent by CYP2C19. The biotransformation is stereoselective. According to the manufacturer, it lowers pH more and longer than omeprazole due to its higher AUC and is more clinically effective. However, in the voucher cell, both agents are equipotent. Thus, the differences are exclusively pharmacokinetic. Whether esomeprazole differs clinically relevantly from omeprazole (antramumps, generics) is controversial. Esomeprazole was launched for commercial reasons probably in the first place because the patent of omeprazole expired. Esomeprazole was still eligible for patent protection.

Indications

Indications include reflux symptoms such as gastric burning and acid regurgitation, reflux esophagitis, GERD, gastroprotection, eradication of Helicobacter pylori, and ulcer disease.

Dosage

According to the SmPC. The usual daily dose in adults is 20-80 mg. It may be increased up to 160 mg depending on the indication. Esomeprazole is dosed higher than omeprazole.

Contraindications

  • Hypersensitivity

For complete precautions, see the drug label.

Interactions

Raising gastric pH may affect the pharmacokinetics of other drugs. Esomeprazole is metabolized by CYP2C19 and inhibits this enzyme. In addition, CYP3A4 is involved in biotransformation.

Adverse effects

The most common adverse effects include headache, digestive symptoms such as abdominal pain, constipation, diarrhea, flatulence, nausea, and vomiting.