Drug

Omeprazole

Synonyms in a broader sense

Proton pump inhibitors, PPIs, active ingredients with the ending -prazole (e.g. pantoprazole), Antra® pump inhibitors

introduction

Normally there is a balance in the stomach between the production of aggressive gastric acid and the protective mechanisms of mucus and hydrogen carbonate formation. The parietal or parietal cells are responsible for the production of gastric acid, the secondary cells for the production of mucus and hydrogen carbonate. Production is regulated by a number of different mechanisms.

The pH value of the acid is usually between 1 and 2 and comes about when an enzyme of the parietal or parietal cells, the H + / K + -ATPase or proton pump, exchanges positively charged hydrogen atoms (protons) for the ion potassium while consuming energy pumps the stomach.

Diseases associated with gastric acid can be influenced in three ways. One possibility is to use antacids to buffer stomach acid. A second possibility is the reconstruction of the mucous membrane protection. The third way aims to reduce gastric acid production. These include the so-called proton pump inhibitors (PPIs) such as the active ingredient omeprazole.

During therapy with omeprazole, attempts should always be made to identify and eliminate the triggering factors for overproduction of gastric acid. Stress and a hectic lifestyle have a positive effect on hydrochloric acid production. Certain luxury foods such as coffee, high percentage alcohol and spicy foods also stimulate production.

It should not be forgotten that a very specific germ called Helicobacter pylori can colonize the gastric mucosa and is the most common cause of gastric and intestinal ulcers and gastric mucosal inflammation. Proton pump inhibitors like omeprazole have supplanted other therapeutic agents like the antacids (which neutralize stomach acid). They are the first choice even before the H2 blockers.

How Omeprazole Works

Proton pump inhibitors such as omeprazole work by binding to the enzyme which is responsible for gastric acid production and thus irreversibly (irreversibly) inhibiting it. As so-called prodrugs, proton pump inhibitors (omeprazole) only work at an acidic pH value and when the parietal cells are active. Only the enzymes that are on the stomach cell membrane are blocked. The active substance (omeprazole) is transported via the bloodstream to the parietal cells, where it accumulates and activates the proton pumps.

Pharmacokinetics of omeprazole

Omeprazole has its site of action on the proton pumps, which are located on the parietal cell membrane and point towards the gastric lumen. In order to reach the parietal cell, however, the substance omeprazole must not be activated in the stomach. Therefore, the drug is administered as an acid-proof capsule. This ensures that the active ingredient is protected from stomach acid by the capsule. Only in the small intestine is the capsule broken by the alkaline intestinal environment and the active ingredient is absorbed into the bloodstream via the intestinal cells. Omeprazole reaches the parietal cell via the blood, where it is activated.

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

Uses of omeprazole

Omeprazole is used for the following diseases:

Inflammation of the stomach lining (hyperacid gastritis)
Gastric and intestinal ulcers (gastric ulcer, duodenal ulcer)
Zollinger-Ellsion Syndrome
Reflux esophagitis (with and without Barrett's syndrome)
Eradication of Helicobacter pylori
Prophylaxis in case of stress or the use of non-steroidal anti-inflammatory drugs (NSAIDs)

Proton pump inhibitors such as omeprazole are used for gastric mucosal inflammation that is related to hydrochloric acid production (hyperacid gastritis), for gastric or small intestinal ulcers (gastric ulcer, duodenal ulcer), an overproduction of the hormone gastrin (Zollinger-Ellison syndrome) and for severe forms of the esophagus which are based on the stomach acid flowing back into the esophagus (reflux esophagitis).

Ompeprazole can also be used for the prophylaxis of stress-related stomach or intestinal ulcers (stress ulcer prophylaxis) or to protect the gastric mucosa during NSAID therapy (non-steroidal anti-inflammatory drugs). These are drugs that relieve pain, reduce fever and reduce inflammation.

In the event of bacterial colonization of the gastric mucosa with the germ Helicobacter pylori, proton pump inhibitors such as omeprazole are used in combination with certain antibiotics. Administration of omeprazole alone without combating the germs usually does not lead to lasting success. In the so-called triple therapy, a proton pump inhibitor, e.g. Omeprazole, 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 the cases. The Helicobacter pylori germ is a gram-negative rod. Up to 50% of the world's population are infected. The infection usually happens in childhood. Re-infection in adulthood is rare (less than 1%).

Side effects of omeprazole

Omeprozole is generally well tolerated. Even when high doses are given and the duration of therapy is long, side effects rarely occur. 1-2% of patients complain of gastrointestinal complaints. As a rule, this is due to a changed bacterial colonization of the gastrointestinal tract, because stomach acid normally ensures that most of the bacteria are killed (e.g. lactobacilli, streptococci).Headache or dizziness are even less common. Some patients also complain of tiredness or itching. In the case of high-dose infusion therapy, as it can be indicated in the case of acute gastric bleeding, in rare cases this leads to visual disturbances, as proton pumps can also be found in the eye.

It must also be noted that certain enzymes, which are responsible for the digestion of proteins in the stomach, can only work optimally if the pH value is correct and there is sufficient hydrochloric acid. This can also lead to digestive disorders, especially when digesting proteins. However, since digestion is generally mainly localized in the small intestine and the stomach portion is rather small, digestive disorders that affect protein digestion in the stomach are not often observed when omeprazole is used alone.

Side effects after discontinuation

After discontinuing omeprazole, there are no direct side effects to be feared and the drug therefore does not have to be tapered. However, if the effect of omeprazole ceases, this can still have consequences. Symptoms that were previously alleviated, such as upper abdominal pain or acid regurgitation, may reappear more intensely after stopping. This can be counteracted by avoiding stimulants that irritate the stomach, such as coffee, alcohol and chocolate, and by not smoking.

Acid blockers such as omeprazole are also often taken preventively to reduce the side effects of other drugs. For example, if omeprazole is stopped while taking medication with painkillers such as ibuprofen or diclofenac, the risk of side effects such as a stomach ulcer increases.

Side effects of long-term medication

So-called “stomach protection” drugs are often prescribed for months or years and taken by the patient. Even if this is also indicated in many cases, the risk of sometimes serious side effects increases with long-term medication.

For one thing, taking omeprazole inhibits the absorption of calcium in the intestines, so the longer the drug is taken, the greater the risk of fractures. This is especially true for older patients who already have bone loss (osteoporosis). The risk of bacterial pneumonia also increases if the drug is used over a long period of time. Another possible consequence of long-term use is inflammation of the kidneys. The side effects mentioned with long-term medication with omeprazole are very dependent on the dosage. In addition, the advantages and disadvantages of long-term medication must always be weighed up.

Interactions of omeprazole with other drugs

Omeprazole may break down other drugs such as diazepam (Psychotropic drugn), phenytoin (used to treat irregular heartbeat or seizures) or warfarin (anticoagulant substance) slow it down.

Omeprazole contraindications

Omeprazole must not be given in severe liver dysfunction.
Another contraindication is the simultaneous administration of clopidogrel. This is an inhibitor of platelet aggregation during coagulation (aggregation). Omeprazole inhibits the enzyme (cytochrome CYP2C19) that activates clopidogrel. This means that a sufficient effective level of clopidogrel cannot be achieved or higher doses are necessary.

What can you do if the effects wear off?

If you feel that the effects of omeprazole are waning or symptoms such as belching or upper abdominal pain become more pronounced, you should see your family doctor or the doctor who prescribed the drug.

It may be necessary to increase the dosage or switch to another drug. In some cases, however, a more detailed examination should first be carried out, e.g. by taking a blood sample. Under no circumstances should the medication of omeprazole be changed or the medication discontinued if the effect wears off.

Can omeprazole be taken during pregnancy?

Omeprazole is usually one of the drugs allowed during pregnancy. However, the doctor who prescribed the drug should be informed of the presence of pregnancy. He will then consider whether or not to prescribe omeprazole.

Often symptoms can also be alleviated by other measures, such as sleeping with an elevated upper body or avoiding coffee and other acid-promoting foods. In principle, no medication should be taken without a doctor's prescription or recommendation, especially during pregnancy.

You may also be interested in this topic: Heartburn during pregnancy

More proton pump inhibitors

In addition to omeprazole, there are currently four other proton pump inhibitors on the market that hardly differ in their mode of action and side effects. These include: