In the U.S.—

In Canada—

• Gastric acid pump inhibitor
• antiulcer agent

Omeprazole (o-MEP-ra-zole ) is used to treat certain conditions in which there is too much acid in the stomach. It is used to treat gastric and duodenal ulcers and gastroesophageal reflux disease, a condition in which the acid in the stomach washes back up into the esophagus. Sometimes omeprazole is used in combination with antibiotics to treat ulcers associated with infection caused by the H. pylori bacteria (germ).

Omeprazole is also used to treat Zollinger-Ellison disease, a condition in which the stomach produces too much acid.

Omeprazole is also used to treat dyspepsia, a condition that causes sour stomach, belching, heart burn, or indigestion.

Omeprazole works by decreasing the amount of acid produced by the stomach.

This medicine is available only with your doctor's prescription.

Oral
• Delayed-release capsules (U.S.)
• Powder for oral suspension (U.S.)
• Delayed-release tablets (Canada)

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For omeprazole, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to omeprazole. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Studies have not been done in humans. However, studies in animals have shown that omeprazole may cause harm to the fetus.

Breast-feeding—Omeprazole may pass into the breast milk. Since this medicine has been shown to cause unwanted effects, such as tumors and cancer in animals, it may be necessary for you to take another medicine or to stop breast-feeding during treatment. Be sure you have discussed the risks and benefits of the medicine with your doctor.

Children—There is no specific information comparing the use of omeprazole in children with use in other age groups.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of omeprazole in the elderly with use in other age groups.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking omeprazole, it is especially important that your health care professional know if you are taking any of the following:

• Anticoagulants (blood thinners) or
• Diazepam (e.g., Valium) or
• Phenytoin (e.g., Dilantin)
• Warfarin (e.g., Coumadin)—Use with omeprazole may cause high blood levels of these medicines, which may increase the chance of side effects

• Liver disease or a history of liver disease—This condition may cause omeprazole to build up in the body

Take omeprazole capsules immediately before a meal, preferably in the morning. Omeprazole tablets may be taken with food or on an empty stomach. Take omeprazole powder for oral suspension on an empty stomach at least 1 hour before a meal.

It may take several days before this medicine begins to relieve stomach pain. To help relieve this pain, antacids may be taken with omeprazole, unless your doctor has told you not to use them.

Swallow the capsule and tablet forms of omeprazole whole. Do not open the capsule. Do not crush, break, or chew the capsule or the tablet.

To use the powder for oral suspension:

• Empty packet of powder into a small cup containing 2 tablespoons of water
• Stir well and drink immediately
• Refill cup with water and drink

Take this medicine for the full time of treatment, even if you begin to feel better. Also, keep your appointments with your doctor for check-ups so that your doctor will be better able to tell you when to stop taking this medicine.

Dosing—

The dose of omeprazole will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of omeprazole. If your dose is different, do not change it unless your doctor tells you to do so.

• For oral dosage forms (capsules, tablets):
  • To treat dyspepsia:
    • Adults—20 milligrams (mg) taken once a day for four weeks. Patients may respond adequately to 10 mg once daily, so individual dose adjustment may be considered.
    • Children—Use and dose must be determined by your doctor.
  • To treat gastroesophageal reflux disease (GERD):
    • Adults—20 milligrams (mg) taken once a day for four to eight weeks. Or your doctor may tell you to take 40 mg a day for certain conditions. Also, your doctor may want you to take omeprazole for more than eight weeks for certain conditions.
    • Children—Use and dose must be determined by your doctor.
  • To treat conditions in which the stomach produces too much acid:
    • Adults—60 mg taken once a day. Your doctor may change the dose as needed. Your treatment may be continued for as long as it is needed.
    • Children—Use and dose must be determined by your doctor.
  • To treat duodenal ulcers:
    • Adults—20 mg taken once a day. Or your doctor may tell you to take 40 mg a day for certain conditions.
    • Children—Use and dose must be determined by your doctor.
  • To treat gastric ulcers:
    • Adults—40 mg taken once a day for four to eight weeks.
    • Children—Use and dose must be determined by your doctor.
  • To treat ulcers related to infection with H. pylori:
    • Adults—40 mg once a day, taken along with clarithromycin 500 mg three times a day, for the first fourteen days. For days 15 through 28, omeprazole 20 mg taken once a day.
    • Children—Use and dose must be determined by your doctor.

• For oral dosage form (powder for suspension):
  • To treat duodenal ulcer:
    • Adults—20 milligrams (mg) taken once a day for four to eight weeks.
    • Children—Use and dose must be determined by your doctor.
  • To treat gastroesophageal reflux disease (GERD) for erosive esophagitis:
    • Adults—20 mg taken once a day for four to eight weeks.
    • Children—Use and dose must be determined by your doctor.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

It is important that your doctor check your progress at regular visits. If your condition does not improve, or if it becomes worse, check with your doctor.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• Rare
  • Back, leg, or stomach pain;  bleeding or crusting sores on lips;  blisters;  bloody or cloudy urine;  chills;  continuing ulcers or sores in mouth;  difficult, burning, or painful urination;  fever;  frequent urge to urinate;  general feeling of discomfort or illness;  joint pain;  loss of appetite;  muscle aches or cramps ;  pain;  red or irritated eyes;  redness, tenderness, itching, burning, or peeling of skin;  skin rash or itching;  sore throat ;  sores, ulcers, or white spots on lips, in mouth, or on genitals;  unusual bleeding or bruising ;  unusual tiredness or weakness 
  
  

• Symptoms of overdose
  • Blurred vision;  confusion;  drowsiness;  dryness of mouth;  fast or irregular heartbeat;  flushing ;  general feeling of discomfort or illness;  headache;  increased sweating;  nausea;  vomiting 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• More common
  • Abdominal or stomach pain 
  
  

• Less common
  • Back pain;  body aches or pain;  chest pain;  constipation;  cough;  diarrhea or loose stools;  difficulty in breathing;  dizziness;  ear congestion;  gas;  headache;  heartburn;  loss of voice;  muscle pain;  nasal congestion;  nausea and vomiting;  runny nose;  skin rash or itching;  sneezing;  unusual drowsiness;  unusual tiredness 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.