Pharmacokinetics of Omeprazole | Omeprazole

Pharmacokinetics of Omeprazole

Omeprazole has its site of action at the proton pumps, which are located at the document cell membrane and point towards the stomach lumen. In order to reach the document cell, however, the substance omeprazole must not already be activated in the stomach. Therefore, the drug is administered as an acid-proof capsule.

This has the effect that the active substance is protected from gastric acid by the capsule. Only in the small intestine is the capsule broken open by the basic intestinal environment and the active ingredient is absorbed into the bloodstream via the intestinal cells. In this way, omeprazole reaches the document cell via the blood, where it is activated.

It should be noted that the drug is broken down relatively quickly in the liver. The half-life of omeprazole is only about one hour. However, since the activated active ingredient irreversibly binds to the proton pump, the duration of action is much longer and the intake of one capsule a day is usually sufficient. The extent to which hydrochloric acid production is inhibited depends on the dose as well as on the number and activity of the proton pumps in the cell membrane of the occupant cells (omeprazole).

Dosage of Omeprazole

Omeprazole is taken orally as an acid-resistant capsule (e.g. Omep®). The usual dose is 20mg per day. In some cases (e.g. Zollinger-Ellison syndrome), however, significantly higher doses may be necessary. Omeprazole has a wide therapeutic range.

Fields of application of Omeprazole

Omeprazole is used for the following diseases:

  • Gastritis (hyperacid gastritis)
  • Gastric and intestinal ulcers (ulcus ventriculi, ulcus duodeni)
  • Zollinger-Ellsion-Syndrome
  • Reflux esophagitis (with and without Barrett’s syndrome)
  • Eradication of Helicobacter pylori
  • Prophylaxis in case of stress or taking non-steroidal anti-inflammatory drugs (NSAIDs)

Proton pump inhibitors such as omeprazole are used for inflammation of the stomach lining associated with hydrochloric acid production (hyperacidic gastritis), for ulcers of the stomach or small intestine (ulcus ventriculi, ulcus duodeni), overproduction of the hormone gastrin (Zollinger-Ellison syndrome) and for severe forms of oesophagitis caused by reflux of stomach acid into the oesophagus (reflux esophagitis). Ompeprazole can also be used for the prophylaxis of stress-related stomach or intestinal ulcers (stress ulcer prophylaxis) or to protect the stomach lining during NSAID therapy (non-steroidal antipholgisitics). These are drugs that have analgesic, antipyretic and anti-inflammatory effects.

In the case of bacterial colonization of the stomach mucosa with the germ Helicobacter pylori, proton pump inhibitors such as omeprazole are used in combination with certain antibiotics. The administration of omeprazole alone without combating the bacteria does not usually lead to lasting success. In the so-called triple therapy, a proton pump inhibitor such as omeprazole is combined with two different antibiotics.

The antibiotics are clarithromycin with either amoxicillin (French triple therapy) or metronidazole (Italian triple therapy). This eradication is successful in more than 90% of cases. The germ Helicobacter pylori is a gram-negative rod.

Up to 50% of the world population is infected. The infection usually occurs in childhood. A new infection in adulthood is rare (less than 1%).