- What is omeprazole, and how does it work (mechanism of action)?
- What brand names are available for omeprazole?
- Is omeprazole available as a generic drug?
- Do I need a prescription for omeprazole?
- What are the side effects of omeprazole?
- What is the dosage for omeprazole?
- Which drugs or supplements interact with omeprazole?
- Is omeprazole safe to take if I'm pregnant or breastfeeding?
- What else should I know about omeprazole?
What is the dosage for omeprazole?
For ulcers, GERD, erosive esophagitis and eradication of H. pylori the recommended dose for adults is 20-40 mg daily. Ulcer healing usually occurs within 4-8 weeks.
H. pylori infections are treated for 10-28 days.
The usual dose for prevention of upper gastrointestinal bleeding in critically ill patients is 40 mg daily for 14 days.
Prilosec OTC is used for treating heartburn for up to two weeks, and the usual dose is 20 mg daily.
For the management of Zollinger-Ellison Syndrome the starting dose for adults is 60 mg daily, and the dose is adjusted based on either the response of symptoms or the actual measurement of acid production. Doses greater than 80 mg should be divided. Doses up to 120 mg three times a day have been used in the treatment of Zollinger-Ellison Syndrome.
For maximal efficacy, omeprazole tablets should be taken before meals, swallowed whole and should not be crushed, chewed or opened.
Which drugs or supplements interact with omeprazole?
The absorption of certain drugs may be affected by stomach acidity. Therefore, omeprazole as well as other PPIs reduce the absorption and concentration in blood of ketoconazole (Nizoral) and increase the absorption and concentration in blood of digoxin (Lanoxin). This may reduce the effectiveness of ketoconazole or increase digoxin toxicity.
Through unknown mechanisms, omeprazole may increase blood levels of saquinavir and reduce blood levels of nelfinavir and atazanavir, drugs that are used for treating patients with infection caused by the human immunodeficiency virus (HIV). Accordingly, the dose of saquinavir may need to be reduced to avoid toxicity, and the doses of nelfinavir and atazanavir may need to be increased to maintain efficacy.
Clopidogrel (Plavix) is converted to its active form by enzymes in the liver. Omeprazole reduces the activity of these enzymes and potentially can reduce the activity of clopidogrel. Omeprazole should not be used with clopidogrel.
Quick GuideHeartburn: Causes, Symptoms, Remedies, Treatments
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Need help identifying pills and medications?
Use the pill identifier tool on RxList.