Omeprazole Magnesium (omeprazole magnesium)

Advertisement

Last reviewed · Source: First Databank (FDB) drug data

Overview

Omeprazole, commonly referred to as an acid- or proton-pump inhibitor, is a gastric antisecretory agent.

Omeprazole is a substituted benzimidazole gastric antisecretory agent. Omeprazole binds to hydrogen/potassium adenosine triphosphatase (H+/K+-exchanging ATPase) in gastric parietal cells; inactivation of this enzyme system (also known as the proton, hydrogen, or acid pump) blocks the final step in the secretion of hydrochloric acid by these cells. Omeprazole inhibits basal and stimulated gastric acid secretion; in addition, because the drug inhibits the final step in the secretory pathway, it inhibits such secretion regardless of the stimulus.

The degree of inhibition of gastric acid secretion is related to the dosage and duration of therapy of omeprazole.

Following oral administration of omeprazole, peak plasma concentrations and AUC are dose proportional up to doses of 40 mg. Peak plasma concentrations and AUC exert a greater than linear response for doses >40 mg because of a saturable first-pass effect. Because the omeprazole molecule is acid labile, the drug is administered orally as a delayed-release capsule or oral suspension or as a buffered immediate-release capsule or oral suspension.

The suspension is also commercially available as a kit containing omeprazole and sodium bicarbonate. The commercially available omeprazole delayed-release capsules increase oral bioavailability of the drug by delaying absorption until after the capsule leaves the stomach; peak plasma concentrations of omeprazole occur 30 minutes to 3.5 hours after administration. The absolute bioavailability of omeprazole delayed-release capsules is 30-40% at doses of 20--40 mg, which is largely due to presystemic metabolism; with repeated administration, bioavailability of the capsules increases slightly.

Following repeated administration of omeprazole magnesium delayed-release oral suspension, peak plasma concentrations are attained within 1.5--2 hours. Mean peak plasma concentrations of omeprazole and sodium bicarbonate preparations occur at about 30 minutes after oral administration. Relative to administration 1 hour before a meal, omeprazole exposure is reduced when omeprazole and sodium bicarbonate preparations are administered 1 hour following a meal.

Following comparable weight-based doses, children 2-5 years of age have lower AUCs than children 6-16 years of age or adults, which are comparable.

Omeprazole is approximately 95% protein bound. Omeprazole undergoes extensive metabolism via the cytochrome P-450 (CYP) enzyme system, primarily via CYP2C19, and to a lesser extent via CYP3A4. Following oral administration of a single dose of omeprazole, approximately 77% of the dose is excreted in urine as various metabolites; the remainder of the dose is excreted in feces.

In healthy individuals, the half-life of delayed-release omeprazole preparations is 30 minutes to 1 hour. The half-life of omeprazole and sodium bicarbonate preparations is approximately 1 hour.

Following oral administration of omeprazole, inhibition of gastric acid secretion is apparent within 1 hour, peaks within 2 hours, and persists for up to 72 hours. Inhibition of gastric acid secretion increases with continuous drug administration and reaches a plateau after about 4 days of omeprazole therapy. Following discontinuance of omeprazole therapy, gastric acid secretion returns to baseline over a 3-5 day period.

USES: Omeprazole is used to treat certain stomach and esophagus problems (such as acid reflux, ulcers). It works by decreasing the amount of acid your stomach makes. It relieves symptoms such as heartburn, difficulty swallowing, and cough.

This medication helps heal acid damage to the stomach and esophagus, helps prevent ulcers, and may help prevent cancer of the esophagus. Omeprazole belongs to a class of drugs known as proton pump inhibitors (PPIs). If you are self-treating with this medication, over-the-counter omeprazole products are used to treat frequent heartburn (occurring 2 or more days a week).

Since it may take 1 to 4 days to have full effect, these products do not relieve heartburn right away. For over-the-counter products, carefully read the package instructions to make sure the product is right for you. Check the ingredients on the label even if you have used the product before.

The manufacturer may have changed the ingredients. Also, products with similar brand names may contain different ingredients meant for different purposes. Taking the wrong product could harm you.

Generic name: omeprazole magnesium
Pronunciation: (oh-MEP-ra-zole)

Reference product & biosimilars

No reference, biosimilar or interchangeable associated with this drug.

Today’s intelligence on Omeprazole Magnesium

Intelligence content is not available yet.

Indications

The following indications are listed for Omeprazole Magnesium:

  • Duodenal Ulcer
  • Duodenal Ulcer Due To H. Pylori
  • Erosive Esophagitis
  • Gastric Hypersecretion With Systemic Mastocytosis
  • Gastric Ulcer
  • Gastroesophageal Reflux Disease
  • Heartburn
  • Helicobacter Pylori Gastritis
  • Maintenance Of Healing Erosive Esophagitis
  • Pathological Gastric Acid Hypersecretory Condition
  • Zollinger-Ellison Syndrome

Also known as: Adenomatosis Partial Multiple Endocrine, Brash, Campylobacter Gastritis, Du Due To H. Pylori, Duodenal Ulcer Due To Campylobacter Pylori, Duodenal Ulcer Due To Helicobacter Pylori, Gastric Acid Hypersecretory Conditions Due To Disease, Gastro-Esophageal Reflux, Ge Reflux Disease, H. Pylori Gastritis, Pancreatic Ulcerogenic Tumor Syndrome, Pathological Gastric Acid Hypersecretory States, Pathological Hypersecretion State, Pathological Hypersecretory Condition, Pyrosis, Systemic Mast Cell Disease With Gastric Hypersecretion, Z-E Syndrome.

Dosing

Dosage of omeprazole magnesium is expressed in terms of omeprazole.

Drug interactions

In vivo, omeprazole is a substrate and inhibitor of cytochrome P-450 (CYP) isoenzyme 2C19, and a substrate of CYP3A4. Omeprazole is also an inhibitor of CYP2C19 in vitro.

When co-packaged delayed-release omeprazole capsules, clarithromycin tablets, and amoxicillin capsules (Omeclamox-Pak(R)) are prescribed, drug interactions should be considered for each individual component. Refer to the Omeclamox-Pak(R) prescribing information for drug interaction information.

Contraindications

*Known hypersensitivity reactions (including anaphylaxis) to omeprazole, esomeprazole, or other substituted benzimidazoles (e.g., lansoprazole, pantoprazole, rabeprazole), or any ingredient in the formulation. Hypersensitivity reactions may include anaphylaxis, anaphylactic shock, angioedema, bronchospasm, acute tubulointerstitial nephritis, and urticaria.

*Concomitant use of proton-pump inhibitors (PPIs), including omeprazole, and rilpivirine is contraindicated.

Adverse reactions

Adverse effects reported in >=2% of adults receiving omeprazole in clinical trials include headache, abdominal pain, nausea, diarrhea, vomiting, and flatulence.

Adverse effects reported in pediatric patients 2--16 years of age receiving omeprazole were similar to those reported in adults, except for more frequently reported respiratory system events and fever.

Precautions

No enhanced messaging available.

ICD codes

No ICD codes are available for this drug.

Formulary status

Search health-plan coverage for this drug by ZIP code.

Enter a ZIP code to view available health plans.

Last reviewed · Source: First Databank (FDB) drug data