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First - Omeprazole (Oral)

Generic name: omeprazole [ oh-MEP-ra-zole ]
Brand names: First - Omeprazole, PriLOSEC, PriLOSEC OTC
Drug class: Proton pump inhibitors

Medically reviewed by Drugs.com. Last updated on Nov 22, 2023.

Uses for First - Omeprazole

Omeprazole is used to treat certain conditions where there is too much acid in the stomach. It is used to treat gastric and duodenal ulcers, erosive esophagitis, and gastroesophageal reflux disease (GERD). GERD is a condition where the acid in the stomach washes back up into the esophagus. Sometimes omeprazole is used in combination with antibiotics (eg, amoxicillin, clarithromycin) to treat ulcers associated with the infection caused by the H. pylori bacteria.

Omeprazole is also used to treat Zollinger-Ellison syndrome, a condition where the stomach produces too much acid.

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

In addition, omeprazole is used to prevent upper gastrointestinal tract bleeding in seriously ill patients.

Omeprazole is a proton pump inhibitor (PPI). It works by decreasing the amount of acid produced by the stomach.

This medicine is available both over-the-counter (OTC) and with your doctor's prescription.

Before using First - Omeprazole

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 this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of omeprazole in children 1 to 16 years of age. Safety and efficacy have not been established in children younger than 1 month of age. .

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of omeprazole in the elderly. However, elderly patients are more sensitive to the effects of this medicine than younger adults.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with 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 this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following may cause an increased risk of certain side effects but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

Proper use of First - Omeprazole

Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered. If you are using this medicine without a prescription, follow the instructions on the medicine label.

This medicine should come with a Medication Guide. Read and follow these instructions carefully. Ask your doctor if you have any questions.

Take omeprazole capsules or delayed-release capsules 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. For patients receiving continuous feeding through a tube, feeding should be temporarily stopped about 3 hours before and 1 hour after administration of omeprazole powder for oral suspension.

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 tells you otherwise.

If you are taking this medicine to treat an ulcer that is associated with an H. pylori infection, take it together with antibiotics (eg, amoxicillin, clarithromycin) at the same time of day.

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.

If you cannot swallow the omeprazole delayed-release capsules, you may open it and sprinkle the pellets contained in the capsule on one tablespoon of applesauce. This mixture must be swallowed immediately with a glass of cool water. The applesauce should not be hot and should be soft enough to be swallowed without chewing. Do not chew or crush the pellets.

To use the powder for oral suspension:

To use the delayed-release oral suspension:

If you are using the delayed-release oral suspension with a nasogastric or gastric tube:

Dosing

The dose of this medicine 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 this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

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

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Detailed Omeprazole dosage information

Precautions while using First - Omeprazole

It is important that your doctor check your or your child's progress at regular visits. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to take it. Blood, urine, and other laboratory tests may be needed to check for unwanted effects. If your or your child's condition does not improve, or if it becomes worse, check with your doctor.

Tell your doctor if you have Asian relatives, such as Filipino, Chinese, Japanese, Korean, or Taiwanese. You may need a lower dose of this medicine to treat erosive esophagitis.

Do not use omeprazole if you are also using medicines containing rilpivirine (Edurant®, Complera®). Using these medicines together may cause unwanted side effects.

This medicine is sometimes given together with other medicines to treat ulcers. Be sure you understand about the risks and proper use of any other medicine your doctor gives you or your child together with omeprazole.

Omeprazole may cause a serious type of allergic reaction when used in patients with conditions treated with antibiotics. Call your doctor right away if you or your child has itching, trouble breathing or swallowing, or any swelling of your hands, face, or mouth.

Check with your doctor right away if you or your child has a change in frequency of urination or amount of urine, blood in the urine, fever, joint pain, loss of appetite, skin rash, swelling of the body, feet, or ankles, unusual tiredness or weakness, or unusual weight gain after receiving this medicine. These could be symptoms of a serious kidney problem called acute tubulointerstitial nephritis.

Taking this medicine for a long time may make it harder for your body to absorb vitamin B12. Tell your doctor if you have concerns about vitamin B12 deficiency.

Serious stomach conditions may occur while taking this medicine alone or together with antibiotics. Check with your doctor immediately if you or your child has stomach cramps, bloated feeling, watery and severe diarrhea which may also be bloody sometimes, fever, nausea or vomiting, or unusual tiredness or weakness.

This medicine may increase your risk of having fractures of the hip, wrist, and spine. This is more likely if you are 50 years of age and older, if you receive high doses of this medicine, or use it for one year or more. Call your doctor right away if you have severe bone pain or are unable to walk or sit normally.

This medicine may cause serious skin reactions, including Stevens-Johnson syndrome, toxic epidermal necrolysis, acute generalized exanthematous pustulosis, and drug reaction with eosinophilia and systemic symptoms (DRESS). Check with your doctor right away if you have black, tarry stools, blistering, peeling, or loosening of the skin, chest pain, chills, cough, diarrhea, itching, joint or muscle pain, painful or difficult urination, red irritated eyes, red skin lesions, often with a purple center, sore throat, sores, ulcers, or white spots in the mouth or on the lips, swollen glands, unusual bleeding or bruising, or unusual tiredness or weakness.

This medicine may cause hypomagnesemia (low magnesium in the blood). This is more likely to occur if you are taking this medicine for more than 1 year, or if you are taking this medicine together with digoxin (Lanoxin®) or certain diuretics or "water pills". Check with your doctor right away if you have convulsions (seizures), fast, racing, or uneven heartbeat, muscle spasms (tetany), tremors, or unusual tiredness or weakness.

Cutaneous or systemic lupus erythematosus may occur or get worse in patients receiving a PPI. Call your doctor right away if you have joint pain or a skin rash on your cheeks or arms that gets worse when exposed to the sun.

This medicine may increase your risk for fundic gland polyps (abnormal tissue growth in the upper part of your stomach). This is more likely if you are receiving this medicine for more than 1 year. Talk to your doctor if you have concerns.

Do not stop taking this medicine without first checking with your doctor, or unless told to do so by your doctor.

Make sure any doctor or dentist who treats you knows that you are using this medicine. You may need to stop using this medicine several days before you have medical tests.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription (eg, atazanavir, nelfinavir, Reyataz®, Viracept®) or nonprescription (over-the-counter [OTC]) medicines and herbal (eg, St. John's wort) or vitamin supplements.

Side Effects of First - Omeprazole

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 immediately if any of the following side effects occur:

Rare

Incidence not known

Get emergency help immediately if any of the following symptoms of overdose occur:

Symptoms of overdose

Some 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. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

Incidence not known

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

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

Omeprazole side effects (more detail)

Commonly used brand name(s)

In the U.S.

Available Dosage Forms:

Therapeutic Class: Gastric Acid Secretion Inhibitor

Pharmacologic Class: Proton Pump Inhibitor

Frequently asked questions

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Further information

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

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