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Omeprazole

Generic Name: omeprazole (oh MEP ra zol)
Brand Names: FIRST Omeprazole, Omeprazole + SyrSpend SF Alka, PriLOSEC, PriLOSEC OTC, Zegerid> (Original Formulation)

Medically reviewed on Sep 13, 2018

What is omeprazole?

Omeprazole is a proton pump inhibitor that decreases the amount of acid produced in the stomach.

Omeprazole is used to treat symptoms of gastroesophageal reflux disease (GERD) and other conditions caused by excess stomach acid. It is also used to promote healing of erosive esophagitis (damage to your esophagus caused by stomach acid).

Omeprazole may also be given together with antibiotics to treat gastric ulcer caused by infection with Helicobacter pylori (H. pylori).

Over-the-counter (OTC) omeprazole is used to help control heartburn that occurs 2 or more days per week. The OTC brand of omeprazole must be taken as a course on a regular basis for 14 days in a row.

Important Information

Omeprazole is not for immediate relief of heartburn symptoms.

Heartburn is often confused with the first symptoms of a heart attack. Seek emergency medical attention if you have chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, and a general ill feeling.

Omeprazole can cause kidney problems. Tell your doctor if you are urinating less than usual, or if you have blood in your urine.

Diarrhea may be a sign of a new infection. Call your doctor if you have diarrhea that is watery or has blood in it.

Omeprazole may cause new or worsening symptoms of lupus. Tell your doctor if you have joint pain and a skin rash on your cheeks or arms that worsens in sunlight.

You may be more likely to have a broken bone while taking omeprazole long term or more than once per day.

Prilosec OTC (over-the-counter) should be taken for no longer than 14 days in a row. Allow at least 4 months to pass before you start another 14-day treatment.

Before taking this medicine

Heartburn can mimic early symptoms of a heart attack. Get emergency medical help if you have chest pain that spreads to your jaw or shoulder and you feel anxious or light-headed.

You should not use omeprazole if you are allergic to it, or if:

Ask a doctor or pharmacist if it is safe for you to use omeprazole if you have other medical conditions, especially:

  • trouble or pain with swallowing;

  • bloody or black stools, vomit that looks like blood or coffee grounds;

  • heartburn that has lasted for over 3 months;

  • frequent chest pain, heartburn with wheezing;

  • unexplained weight loss;

  • nausea or vomiting, stomach pain;

  • liver disease;

  • low levels of magnesium in your blood; or

  • osteoporosis or low bone mineral density (osteopenia).

You may be more likely to have a broken bone in your hip, wrist, or spine while taking a proton pump inhibitor long-term or more than once per day. Talk with your doctor about ways to keep your bones healthy.

Ask a doctor before using omeprazole if you are pregnant or breast-feeding.

Do not give this medicine to a child without medical advice.

How should I take omeprazole?

Omeprazole is usually taken before eating (at least 1 hour before a meal). Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Use Prilosec OTC (over-the-counter) exactly as directed on the label, or as prescribed by your doctor.

Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you do not understand these instructions.

Shake the oral suspension (liquid) before you measure a dose. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

If you cannot swallow a capsule whole, open it and sprinkle the medicine into a spoonful of applesauce. Swallow the mixture right away without chewing. Do not save it for later use.

You must dissolve omeprazole powder in a small amount of water. This mixture can either be swallowed or given through a nasogastric (NG) feeding tube using a catheter-tipped syringe.

OTC omeprazole should be taken for only 14 days in a row. Allow at least 4 months to pass before you start a new 14-day course of treatment.

Use this medicine for the full prescribed length of time, even if your symptoms quickly improve.

Call your doctor if your symptoms do not improve, or if they get worse.

Some conditions are treated with a combination of omeprazole and antibiotics. Use all medications as directed.

Omeprazole can affect the results of certain medical tests. Tell any doctor who treats you that you are using this medicine.

Store at room temperature away from moisture and heat.

Omeprazole dosing information

Usual Adult Dose of Omeprazole for Duodenal Ulcer:

20 mg orally once a day
-Duration of therapy: 4 weeks

Comment: If patients are not fully healed after 4 weeks, treatment may continue for another 4 weeks.

Use: Short-term treatment of active duodenal ulcer

Usual Adult Dose of Omeprazole for Helicobacter pylori Infection:

Dual therapy: 40 mg orally once a day, taken concomitantly with clarithromycin
-Duration of therapy: 14 days

Triple therapy: 20 mg orally 2 times a day, taken concomitantly with amoxicillin and clarithromycin
-Duration of therapy: 10 days

Comments:
-Patients presenting with an ulcer at the time of treatment should continue treatment with a 20 mg dose orally once a day for 14 days (dual therapy) or 18 days (triple therapy).
-Antibiotic selection should be determined by local bacterial resistance, duration of treatment, and appropriate use.
-Refer to the manufacturer product information for dosing for amoxicillin and/or clarithromycin.

Uses: Helicobacter pylori eradication to reduce the risk of duodenal ulcer recurrence
-TRIPLE THERAPY: Treatment of patients with H pylori infection and active or a history of duodenal ulcer disease (within 1 year)
-DUAL THERAPY: Treatment of patients with H pylori infection and duodenal ulcer disease

Usual Adult Dose for Gastric Ulcer:

40 mg orally once a day
-Duration of therapy: 4 to 8 weeks

Use: Short-term treatment of active benign gastric ulcer

Usual Adult Dose of Omeprazole for Erosive Esophagitis:

Treatment: 20 mg orally once a day
-Duration of therapy: 4 to 8 weeks

Maintenance: 20 mg orally once a day

Comments:
-Controlled studies for maintenance therapy did not extend past 12 months.
-Patients who do not respond after 8 weeks of treatment may continue for an additional 4 weeks.
-If there is a recurrence of erosive esophagitis (EE) or gastroesophageal reflux disease (GERD) symptoms, an additional 4 to 8 week course of treatment should be considered.

Uses:
-Treatment of EE due to acid-mediated GERD
-Maintenance of healing of EE due to acid-mediated GERD

Usual Adult Dose for Multiple Endocrine Adenomas:

Initial dose: 60 mg orally once a day
Maximum dose: 360 mg/day (as 120 mg orally 3 times a day)

Comments:
-Doses higher than 80 mg should be given in divided doses.
-The treatment duration should be for as long as clinically necessary. Some patients with Zollinger-Ellison Syndrome have been treated for longer than 5 years.

Use: Long-term treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, multiple endocrine adenomas, systemic mastocytosis)

Usual Adult Dose for Systemic Mastocytosis:

Initial dose: 60 mg orally once a day
Maximum dose: 360 mg/day (as 120 mg orally 3 times a day)

Comments:
-Doses higher than 80 mg should be given in divided doses.
-The treatment duration should be for as long as clinically necessary. Some patients with Zollinger-Ellison Syndrome have been treated for longer than 5 years.

Use: Long-term treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, multiple endocrine adenomas, systemic mastocytosis)

Usual Adult Dose for Zollinger-Ellison Syndrome:

Initial dose: 60 mg orally once a day
Maximum dose: 360 mg/day (as 120 mg orally 3 times a day)

Comments:
-Doses higher than 80 mg should be given in divided doses.
-The treatment duration should be for as long as clinically necessary. Some patients with Zollinger-Ellison Syndrome have been treated for longer than 5 years.

Use: Long-term treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, multiple endocrine adenomas, systemic mastocytosis)

Usual Adult Dose for Hypersecretory Conditions:

Initial dose: 60 mg orally once a day
Maximum dose: 360 mg/day (as 120 mg orally 3 times a day)

Comments:
-Doses higher than 80 mg should be given in divided doses.
-The treatment duration should be for as long as clinically necessary. Some patients with Zollinger-Ellison Syndrome have been treated for longer than 5 years.

Use: Long-term treatment of pathological hypersecretory conditions (e.g., Zollinger-Ellison syndrome, multiple endocrine adenomas, systemic mastocytosis)

Usual Adult Dose for Gastroesophageal Reflux Disease:

20 mg orally once a day
-Duration of therapy: Up to 4 weeks

Use: Treatment of symptomatic GERD

Usual Adult Dose for Dyspepsia:

Over-the-Counter (OTC) formulations:
-Recommended dose: 20 mg orally once a day in the morning
-Duration of therapy: 14 days

Comments:
-A 14-day course of treatment may be repeated every 4 months.
-This drug should be taken with a full glass of water prior to eating.

Use:
-Treatment for frequent heartburn (occurring 2 or more days a week)

Usual Pediatric Dose for Gastroesophageal Reflux Disease:

1 to 16 years:
5 to less than 10 kg: 5 mg orally once a day
10 to less than 20 kg: 10 mg orally once a day
20 kg and greater: 20 mg orally once a day
Duration of therapy: Up to 4 weeks

16 to 18 years: 20 mg orally once a day
-Duration of therapy: Up to 4 weeks

Use: Treatment of symptomatic GERD

Usual Pediatric Dose for Erosive Esophagitis:

TREATMENT:
1 month to less than 1 year:
3 to less than 5 kg: 2.5 mg orally once a day
5 to less than 10 kg: 5 mg orally once a day
10 kg and greater: 10 mg orally once a day
Duration of therapy: Up to 6 weeks

1 to 16 years:
5 to less than 10 kg: 5 mg orally once a day
10 to less than 20 kg: 10 mg orally once a day
20 kg and greater: 20 mg orally once a day
Duration of therapy: 4 to 8 weeks

16 to 18 years: 20 mg orally once a day
-Duration of therapy: 4 to 8 weeks

MAINTENANCE:
1 to 16 years:
5 to less than 10 kg: 5 mg orally once a day
10 to less than 20 kg: 10 mg orally once a day
20 kg and greater: 20 mg orally once a day

16 to 18 years: 20 mg orally once a day

Comments:
-Patients who do not respond after 8 weeks of treatment may continue for an additional 4 weeks.
-If there is a recurrence of EE or GERD symptoms, an additional 4 to 8 week course of treatment should be considered.
-Controlled studies for maintenance therapy did not extend past 8 weeks.

Uses:
-Treatment of EE due to acid-mediated GERD
-Maintenance of healing of EE due to acid-mediated GERD

See also: Dosage Information (in more detail)

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking omeprazole?

Omeprazole can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, call your doctor before using anti-diarrhea medicine.

Omeprazole side effects

Get emergency medical help if you have signs of an allergic reaction to omeprazole: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using omeprazole and call your doctor at once if you have:

  • severe stomach pain, diarrhea that is watery or bloody;

  • new or unusual pain in your wrist, thigh, hip, or back;

  • seizure (convulsions);

  • kidney problems - little or no urination, blood in your urine, swelling, rapid weight gain;

  • low magnesium - dizziness, fast or irregular heart rate, tremors (shaking) or jerking muscle movements, feeling jittery, muscle cramps, muscle spasms in your hands and feet, cough or choking feeling; or

  • new or worsening symptoms of lupus - joint pain, and a skin rash on your cheeks or arms that worsens in sunlight.

Taking this medicine long-term may cause you to develop stomach growths called fundic gland polyps. Talk with your doctor about this risk.

If you use omeprazole for longer than 3 years, you could develop a vitamin B-12 deficiency. Talk to your doctor about how to manage this condition if you develop it.

Common omeprazole side effects may include:

  • stomach pain, gas;

  • nausea, vomiting, diarrhea; or

  • headache.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect omeprazole?

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Tell your doctor about all your current medicines. Many drugs can interact qomeprazole, especially:

This list is not complete and many other drugs may affect omeprazole. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use omeprazole only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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