Omeprazole works by blocking acid production in the stomach. This medication is known as a proton pump inhibitor (PPI). It is used to treat acid-related stomach and throat (esophagus) problems (e.g., acid reflux or GERD, ulcers, erosive esophagitis, or Zollinger-Ellison Syndrome). Decreasing excess stomach acid can help relieve symptoms such as heartburn, difficulty swallowing, persistent cough, and trouble sleeping. It can also prevent serious acid damage to your digestive system (e.g., ulcers, cancer of the esophagus).

This medication may be used in combination with antibiotics to treat certain types of ulcers caused by bacterial infection.

Take this medication by mouth, usually once daily, before a meal; or as directed by your doctor.

Do not crush, break or chew the medication. Swallow the medication whole. If you have difficulty swallowing this medication whole, the capsule may be opened and the contents sprinkled onto cool applesauce and taken as directed. Do not chew the food/medication mixture or prepare a supply in advance; this may destroy the drug and/or increase side effects. Drink a glass of cool water after each dose to ensure complete swallowing of the medication.

Antacids may be taken along with this medication, if needed.

The dosage and length of treatment is based on your medical condition and response to therapy.

Use this medication regularly in order to get the most benefit from it. Remember to use it at the same time each day. Continue to take this medication for the prescribed length of treatment even if you are feeling better.

Inform your doctor if your condition persists or worsens.

Constipation, cough, dizziness or back pain may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor immediately if any of these highly unlikely but very serious side effects occur: signs of vitamin B-12 deficiency with long-term (over 3 years) treatment (e.g., unusual weakness, sore tongue, numbness or tingling of the hands/feet).

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking omeprazole, tell your doctor or pharmacist if you are allergic to it; or to similar drugs (e.g., lansoprazole, pantoprazole); or if you have any other allergies.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: liver disease, other stomach problems (e.g., tumors).

Some symptoms may actually be signs of a more serious condition. Tell your doctor immediately if you have: heartburn combined with lightheadedness/sweating/dizziness, chest pain or shoulder/jaw pain (especially with trouble breathing), pain spreading to arms/neck/shoulders, unexplained weight loss.

This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.

This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.

This medication passes into breast milk. Breast-feeding while using this drug is not recommended. Consult your doctor before breast-feeding.

Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious interactions may occur: atazanavir, nelfinavir.

If you are currently using any of these medications, tell your doctor or pharmacist before starting omeprazole.

Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: certain drugs to suppress the immune system (e.g., cyclosporine, tacrolimus), cilostazol, clopidogrel, diazepam, disulfiram, phenytoin, saquinavir, tipranavir, voriconazole, warfarin.

Some products need stomach acid so that the body can absorb them properly (such as ampicillin, iron supplements, calcium supplements, dasatinib, azole antifungals including ketoconazole). Omeprazole decreases stomach acid, so it may change how well these other products work. Before using omeprazole, consult your doctor or pharmacist about the other medications you take and for advice on how to reduce or avoid these types of interactions.

Based on information for similar drugs, omeprazole may increase the amount of digoxin that is absorbed into your blood. Consult your doctor or pharmacist for details if you also take digoxin.

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

If overdose is suspected, contact your local poison control center or emergency room immediately. US residents can call the US national poison hotline at 1-800-222-1222. Canadian residents should call their local poison control center directly. Symptoms of overdose may include: confusion, unusual sweating, blurred vision, unusually fast heartbeat.

Do not share this medication with others. Laboratory and/or medical tests may be performed to monitor your progress or check for side effects.

If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

Store at room temperature between 59-86 degrees F (15-30 degrees C) away from light and moisture. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

Information last revised July 2009 Copyright(c) 2009 First DataBank, Inc.