omeprazole, omeprazole/sodium bicarbonate, Prilosec, Zegerid (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

For maximal efficacy, omeprazole tablets should be taken before meals, swallowed whole and should not be crushed, chewed or opened.

DRUG INTERACTIONS: Omeprazole potentially can increase the concentrations in blood of diazepam (Valium), warfarin (Coumadin), and phenytoin (Dilantin) by decreasing the elimination of these drugs by the liver.

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.

Omeprazole increases the concentration of cilostazol (Pletal). The dose of cilostazol should be reduced from 100 mg twice daily to 50 mg twice daily when given with omeprazole.

PREGNANCY: Use of omeprazole in pregnant women has not been adequately evaluated. Omeprazole should be used during pregnancy only if the benefits justify the unknown risks.

NURSING MOTHERS: Omeprazole is excreted in breast milk and potentially could cause adverse effects in the infant.

Reference: FDA Prescribing Information


Medically Reviewed by a Doctor on 12/12/2014


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