Omeprazole

Brand names

• Losec
• Prilosec

Usage

To treat gastric and duodenal ulcers, as well as conditions that cause increased stomach acid production (such as Zollinger-Ellison syndrome), erosive esophagitis (severe, chronic inflammation of the esophagus), and gastroesophageal reflux (backwash of stomach acid into the esophagus, resulting in heartburn). Also used to treat NSAID-associated ulcers and in the eradication of Helicobacter pylori (in combination with antibiotics).

How it works

Omeprazole blocks the action of a specific enzyme in the cells that line the stomach, thereby decreasing the production of stomach acid. Reduction of stomach acid promotes healing of ulcers.

Side effects

Serious

No serious side effects are associated with this medication.

Common

Diarrhea, constipation, vomiting, headache, dizziness, stomach pain. Consult your physician if such side effects persist or interfere with daily activities.

Less common

Bloody or cloudy urine, persistent or recurring sores or ulcers in the mouth, painful or very frequent urination, sore throat, fever, unusual bruising or bleeding, unusual weakness or tiredness, muscle pain, chest pain, nausea. Consult your doctor if such symptoms occur.

Possible interactions

Other medicaments:

Omeprazole may increase the effects of:

• anticoagulants (warfarin, etc.) and increase the risk of bleeding.
• carbamazepine (Tegretol).
• clonazepam (Klonopin) and some other benzodiazepines and lead to benzodiazepine toxicity.
• cyclosporine (Sandimmune), by increasing its level (decreased levels also reported).
• diazepam (Valium) and cause excessive sedation.
• digoxin (Lanoxin) and lead to toxicity.
• disulfiram (Antabuse).
• fluvastatin (Lescol).
• methotrexate (Rheumatrex).
• phenytoin (Dilantin, etc.) or fosphenytoin (Cerebyx) and cause phenytoin or fosphenytoin toxicity.
• warfarin (Coumadin) and lead to bleeding; more frequent INR (prothrombin time or protime) testing is needed. Warfarin doses should be adjusted according to laboratory results.

Omeprazole may decrease the effects of:



• amoxicillin (various).
• ampicillin (various).
• iron preparations.
• itraconazole (Sporanox).
• ketoconazole (Nizoral).
• olanzapine (Zyprexa).
• ritonavir (Norvir)-may also increase omeprazole effects.
• trovafloxacin (Trovan).

Herbal medicines or minerals:

Kola and ma huang may increase stomach acid, blunting the benefits of this medicine. Black cohosh root, ginkgo and squill are contraindicated in gastrointestinal disturbances. Licorice root has a Commission E monograph indication for gastrointestinal ulcers. Talk to your doctor before adding any herbals to these medicines.

Tobacco smoking:

Smoking may stimulate the secretion of stomach acid.

Discontinuation:

The duration of use will vary according to the condition under treatment and individual patient response. Premature discontinuation could result in incomplete healing or prompt recurrence of symptoms.