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URL of this page: https://medlineplus.gov/druginfo/meds/a693050.html

Omeprazole

pronounced as (oh me' pray zol)

Why is this medication prescribed?

Prescription omeprazole is used alone or with other medications to treat the symptoms of gastroesophageal reflux disease (GERD), a condition in which backward flow of acid from the stomach causes heartburn and possible injury of the esophagus (the tube between the throat and stomach) in adults and children 1 year of age and older. Prescription omeprazole is used to treat damage from GERD in adults and children 1 month of age and older. Prescription omeprazole is used to allow the esophagus to heal and prevent further damage to the esophagus in adults and children 1 year of age and older with GERD. Prescription omeprazole is also used to treat conditions in which the stomach produces too much acid such as Zollinger-Ellison syndrome in adults. Prescription omeprazole is also used to treat ulcers (sores in the lining of the stomach or intestine) and it is also used with other medications to treat and prevent the return of ulcers caused by a certain type of bacteria (H. pylori) in adults. Nonprescription (over-the-counter) omeprazole is used to treat frequent heartburn (heartburn that occurs at least 2 or more days a week) in adults. Omeprazole is in a class of medications called proton-pump inhibitors. It works by decreasing the amount of acid made in the stomach.

How should this medicine be used?

Prescription omeprazole comes as a delayed-release (releases the medication in the intestine to prevent break-down of the medication by stomach acids) capsule, and packets of delayed-release (releases the medication in the intestine to prevent break-down of the medication by stomach acids) granules for suspension (to be mixed with liquid) to take by mouth or give through a feeding tube. Nonprescription (over-the-counter) omeprazole comes as a delayed-release tablet to take by mouth. Prescription omeprazole is usually taken once a day before a meal but may be taken twice a day when used with other medications to eliminate H. pylori, or up to three times a day, before meals when used to treat conditions in which the stomach produces too much acid. The nonprescription delayed-release tablets are usually taken once a day in the morning at least 1 hour before eating for 14 days in a row. If needed, additional 14-day treatments may be repeated, not more often than once every 4 months. To help you remember to take omeprazole, take it at around the same time(s) every day. Follow the directions on your prescription label or the package label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take omeprazole exactly as directed. Do not take more or less of it or take it more often or for a longer period of time than prescribed by your doctor or stated on the package.

If you are taking the delayed-release tablets, swallow them whole with a full glass of water. Do not split, chew, or crush them or crush and mix them into food.

Swallow the delayed-release capsules whole. If you have difficulty swallowing the delayed-release capsules, place one tablespoon of soft, cool applesauce in an empty bowl. Open the delayed-release capsule and carefully empty all the granules inside the capsule onto the applesauce. Mix the granules with the applesauce and swallow the mixture immediately with a glass of cool water. Do not chew or crush the granules. Do not store the applesauce/granule mixture for future use.

If you are taking the granules for oral suspension, you will need to mix it with water before use. If you are using the 2.5-mg packet, place 1 teaspoonful (5 mL) of water in a container. If you are using the 10-mg packet, place 1 tablespoonful (15 mL) of water in a container. Add the contents of the powder packet and stir. Wait 2 to 3 minutes to allow the mixture to thicken, and stir the mixture again. Drink the entire mixture within 30 minutes. If any of the mixture is stuck to the container, pour more water into the container, stir and drink all the mixture immediately.

The granules for oral suspension can be given through a feeding tube. If you have a feeding tube, ask your doctor how you should take the medication. Follow the directions carefully.

Do not take nonprescription omeprazole for immediate relief of heartburn symptoms. It may take 1 to 4 days for you to feel the full benefit of the medication. Call your doctor if your symptoms get worse or do not improve after 14 days or if your symptoms return sooner than 4 months after you finish your treatment. Do not take nonprescription omeprazole for longer than 14 days or treat yourself with omeprazole more often than once every 4 months without talking to your doctor.

Continue to take prescription omeprazole even if you feel well. Do not stop taking prescription omeprazole without talking to your doctor. If your condition does not improve or gets worse, call your doctor.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking omeprazole,

  • tell your doctor and pharmacist if you are allergic to omeprazole, dexlansoprazole (Dexilant), esomeprazole (Nexium), lansoprazole (Prevacid), pantoprazole (Protonix), rabeprazole (Aciphex), any other medications, or any of the ingredients in the omeprazole product you will be taking. Ask your pharmacist or check the package label for a list of the ingredients.
  • Some medications should not be taken with omeprazole. Other medications may cause dosing changes or extra monitoring when taken with omeprazole. Make sure you have discussed any medications you are currently taking or plan to take before starting omeprazole with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking omeprazole, please get the advice of your doctor or pharmacist.
  • The following nonprescription or herbal products may interact with omeprazole: iron supplements, St. John's wort. Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking omeprazole. Do not start any of these medications while taking omeprazole without discussing with your healthcare provider.
  • if you plan to take nonprescription omeprazole, tell your doctor if your heartburn has lasted 3 months or longer, if you have taken nonprescription omeprazole for a longer period of time than stated on the package, or if you have experienced any of the following symptoms: lightheadedness, sweating, or dizziness along with your heartburn; chest pain or shoulder pain; shortness of breath or wheezing; pain that spreads to your arms, neck, or shoulders; unexplained weight loss; nausea; vomiting, especially if the vomit is bloody; stomach pain; difficulty swallowing food or pain when you swallow food; or black or bloody stools. You may have a more serious condition that cannot be treated with nonprescription medication.
  • tell your doctor if you are of Asian descent and if you have or have ever had a low level of magnesium, calcium, or potassium in your blood; hypoparathyroidism (condition in which the body does not produce enough parathyroid hormone [PTH; a natural substance needed to control the amount of calcium in the blood]); low levels of vitamin B12 in your body; osteoporosis (a condition in which the bones become thin and weak and break easily); an autoimmune disease (condition in which the body attacks its own organs, causing swelling and loss of function) such as systemic lupus erythematosus; or liver disease.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Omeprazole may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • constipation
  • gas
  • nausea
  • diarrhea
  • vomiting
  • headache
  • in men, difficulty achieving or maintaining an erection

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately, or get emergency medical help:

  • blisters, peeling, or bleeding skin; sores on the lips, nose, mouth, or genitals; swollen glands; shortness of breath; fever; or flu-like symptoms
  • rash; hives; itching; swelling of the eyes, face, lips, mouth, throat, or tongue; difficulty breathing or swallowing; or hoarseness
  • irregular, fast, or pounding heartbeat; muscle spasms; uncontrollable shaking of a part of the body; excessive tiredness; lightheadedness; dizziness; or seizures
  • severe diarrhea with watery stools, stomach pain, or fever that does not go away
  • new or worsening joint pain; rash on cheeks or arms that is sensitive to sunlight
  • increased or decreased urination, blood in urine, fatigue, nausea, loss of appetite, fever, rash, or joint pain

People who take proton pump inhibitors such as omeprazole may be more likely to fracture their wrists, hips, or spine than people who do not take one of these medications. People who take proton pump inhibitors may also develop fundic gland polyps (a type of growth on the stomach lining). These risks are highest in people who take high doses of one of these medications or take them for one year or longer. Talk to your doctor about the risk of taking omeprazole.

Omeprazole may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from light, excess heat, and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

  • confusion
  • drowsiness
  • blurred vision
  • fast or pounding heartbeat
  • nausea
  • vomiting
  • sweating
  • flushing (feeling of warmth)
  • headache
  • dry mouth

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor may order certain laboratory tests before and during your treatment.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are taking omeprazole.

Do not let anyone else take your medication. If you are taking prescription omeprazole, ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Prilosec®
  • Prilosec® OTC
  • Talicia (as a combination product containing Amoxicillin, Omeprazole, Rifabutin)

Brand names of combination products

  • Zegerid® (containing Omeprazole, Sodium Bicarbonate)
  • Zegerid® OTC (containing Omeprazole, Sodium Bicarbonate)
Last Revised - 11/15/2023