What is omeprazole

Omeprazole reduces the amount of acid your stomach makes. It’s a widely-used treatment for indigestion and acid reflux. Omeprazole is also taken to prevent and treat stomach ulcers. Omeprazole OTC (over-the-counter) is nonprescription omeprazole that is used to treat frequent heartburn (heartburn that occurs at least 2 or more days a week). Omeprazole is in a class of medications called proton-pump inhibitors (PPIs). Omeprazole works by decreasing the amount of stomach acid made by glands in the lining of your stomach. On the other hand, prescription omeprazole is used alone or with other medications to treat 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). Prescription omeprazole is used to treat the symptoms of GERD, allowing the esophagus to heal, and preventing further damage to the esophagus. Prescription omeprazole is also used to treat conditions in which the stomach produces too much acid such as Zollinger-Ellison syndrome. Zollinger-Ellison syndrome is a condition in which the body produces too much of the hormone gastrin. Most of the time, a small tumor (gastrinoma) in the pancreas or small intestine is the source of the extra gastrin in the blood. 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 (Helicobacter pylori).

Key facts

• It’s usual to take omeprazole once a day in the morning.
• For severe illness, you can take it twice a day – in the morning and in the evening.
• Common side effects include headaches, diarrhoea and stomach pain. These tend to be mild and go away when you stop taking the medicine.
• If you’re self-treating with omeprazole, don’t take it for longer than 2 weeks without checking with a doctor.
• Omeprazole is also called by the brand names Prilosec®, Prilosec® OTC, Losec and Losec MUPS.

How to take omeprazole

It’s usual to take omeprazole once a day, first thing in the morning. It doesn’t upset the stomach so you can take it with or without food.

When to take omeprazole

If you take omeprazole twice a day, take one dose in the morning and one dose in the evening.

What does omeprazole do?

Omeprazole is a type of medicine called a proton pump inhibitor (PPI). Proton pumps are tiny substances in the lining of the stomach which help it make acid.

Omeprazole prevents proton pumps from working properly. This reduces the amount of acid the stomach makes.

Can lifestyle changes help?

It may be possible to ease symptoms caused by too much stomach acid by making a few changes to your diet and lifestyle:

• lose excess weight
• don’t eat foods that can make your symptoms worse, such as rich, spicy and fatty foods, and acidic foods like tomatoes, citrus fruits, salad dressings and fizzy drinks
• cut down on caffeinated drinks, such as tea, coffee and cola, as well as alcohol and smoking
• if you have symptoms at night, try not to eat for at least 3 hours before you go to bed
• raise the head of your bed a little

Can I drink alcohol with omeprazole?

Alcohol doesn’t interfere with the way omeprazole works. However, drinking alcohol makes your stomach produce more acid than normal. This can irritate your stomach lining and make your symptoms worse.

Can I drive or ride a bike?

Omeprazole can make you feel dizzy, sleepy, or get blurred vision. If this happens to you, don’t drive, cycle or use machinery or tools until you feel better.

How long does it take for omeprazole to work?

You should start to feel better within 2 to 3 days. It may take up to 4 weeks for omeprazole to work properly so you may still have some acid symptoms during this time.

If you are self-treating, tell your doctor if you feel no better after taking omeprazole for 2 weeks. They may want to do tests or change you to a different medicine.

How long will I take omeprazole for?

Depending on your illness or the reason you’re taking omeprazole, you may only need it for a few weeks or months. Sometimes you might need to take it for longer, even for many years.

Some people don’t need to take omeprazole every day and take it only when they have symptoms. Once you feel better (often after a few days or weeks), you can stop taking it. However, taking omeprazole in this way isn’t suitable for everyone. Talk to your doctor about what is best for you.

Is it safe to take omeprazole for a long time?

If you take omeprazole for more than 3 months, the levels of magnesium in your blood may fall. Low magnesium can make you feel tired, confused, dizzy and cause muscle twitches, shakiness and an irregular heartbeat. If you get any of these symptoms, tell your doctor.

Taking omeprazole for more than a year may increase your chances of certain side effects, including:

• bone fractures
• gut infections
• vitamin B12 deficiency – symptoms include feeling very tired, a sore and red tongue, mouth ulcers and pins and needles

If you take omeprazole for longer than 1 year your doctor will regularly check your health to see if you should carry on taking it.

It’s not known if omeprazole works less well the longer you take it. If you feel like omeprazole is not working any more, talk to your doctor.

How do I come off omeprazole?

Usually, you can stop taking omeprazole without reducing the dose first.

If you’ve taken omeprazole for a long time speak to your doctor before you stop taking it. Stopping suddenly could make your stomach produce a lot more acid, and make your symptoms come back. Reducing the dose gradually before stopping completely will prevent this happening.

Is omeprazole I buy over-the-counter the same as on prescription?

You can buy omeprazole 10mg tablets and capsules from pharmacies. They’re the same as omeprazole 10mg tablets and capsules you get on prescription, but they’re meant to be taken only by adults and only for up to 4 weeks.

Higher doses of omeprazole are only available on prescription.

Will my omeprazole dose go up or down?

Sometimes your doctor will increase your dose of omeprazole if it isn’t working well enough.

Depending on the reason you take omeprazole, you may take a higher dose to begin with, usually for a month or two. After this, your doctor may recommend that you take a lower dose.

Are there other indigestion medicines?

There are other pharmacy and prescription medicines for indigestion and heartburn.

Antacids, like calcium carbonate (Tums), sodium bicarbonate, Maalox and Milk of Magnesia, relieve indigestion and heartburn by neutralising the acid in your stomach. They give quick relief that lasts for a few hours. They’re ideal for occasional bouts of stomach acid symptoms.

Some antacids, such as Gaviscon, have an extra ingredient called alginic acid. They work by lining your stomach so that juices from it don’t splash up into your foodpipe. They’re especially good for relieving acid reflux.

Antacids are available from pharmacies and supermarkets.

Histamine antagonists (commonly called H2 blockers) reduce the amount of acid made in your stomach, but they do this in a different way to PPIs.

They include ranitidine (Zantac), cimetidine (Tagamet), famotidine (Pepcid) and nizatidine (Axid).

In general, proton pump inhibitors like omeprazole are used first because they are better than H2 blockers at reducing stomach acid. However, if you don’t get on with a proton pump inhibitor (for example, because of side effects), your doctor may prescribe an H2 blocker.

You can buy famotidine and ranitidine over the counter from pharmacies.

Can I take omeprazole with an antacid?

You can take omeprazole with an antacid, for example Gaviscon, if you need to but leave a gap of 2 hours between them.

How should omeprazole be used?

Omeprazole over-the-counter (nonprescription) comes as a delayed-release capsule or tablet to take by mouth. The delayed-release capsules and the granules should be taken at least 1 hour before a meal. They are usually taken once a day before a meal but may be taken twice a day when used with other medications to eliminate Helicobacter pylori or up to three times a day when used to treat conditions in which the stomach produces too much acid. Omeprazole over-the-counter (nonprescription) delayed-release tablets or capsules are usually taken once a day in the morning at least 1 hour before eating for 14 days in a row. Additional 14-day treatments may be repeated once every 4 months if needed. To help you remember to take omeprazole, take it at around the same time(s) every day. Tell your doctor if you have taken nonprescription omeprazole for a longer period of time than stated on the package.

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. 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 powder 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 powder and the contents of the prescription delayed-release capsules can both 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 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.

Who can and can’t take omeprazole

Omeprazole can be taken by adults including pregnant and breastfeeding women.

Omeprazole can be taken by children and babies if it’s been prescribed by a doctor.

Some omeprazole capsules contain gelatin so they’re not suitable for vegetarians and vegans.

Some omeprazole capsules contain small amounts of lactose, so they may be unsuitable for people with a digestive problem called lactose intolerance.

To make sure omeprazole is safe for you, tell your doctor if you have:

• had an allergic reaction to omeprazole or any other medicines in the past
• liver problems

Omeprazole special precautions

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.

• tell your doctor if you are taking rilpivirine (Edurant, in Complera, Odefsey). Your doctor will probably tell you not to take omeprazole if you are taking this medication.

• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: certain antibiotics, including ampicillin (Principen, in Unasyn);anticoagulants (‘blood thinners’) such as warfarin (Coumadin); atazanavir (Reyataz); benzodiazepines such as diazepam (Valium); cilostazol (Pletal); clopidogrel (Plavix); cyclosporine (Neoral, Sandimmune); digoxin (Lanoxicaps, Lanoxin) disulfiram (Antabuse); diuretics (‘water pills’); iron supplements; ketoconazole (Nizoral); methotrexate (Rheumatrex, Trexall), nelfinavir (Viracept); phenytoin (Dilantin); saquinavir (Invirase); tacrolimus (Prograf); and voriconazole (Vfend) and other prescription antifungal or anti-yeast medications. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.

• if you plan to take nonprescription omeprazole, tell your doctor if your heartburn has lasted 3 months or longer 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 in your blood or liver disease.

• if you are 50 years of age or older, ask your doctor if it is safe for you to take nonprescription or prescription omeprazole. The risk that you may develop a severe form of diarrhea caused by bacteria or that you may fracture your wrist, hip, or spine may be higher if you are an older adult.

• tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking omeprazole, call your doctor.

Pregnancy and breastfeeding

Usually, omeprazole is safe to take during pregnancy and while breastfeeding.

If you’re pregnant, it’s always better to try to treat indigestion without taking a medicine.

Your doctor or midwife will first advise that you try to ease your symptoms by eating smaller meals more often, not eating fatty and spicy foods, and raising the head of your bed a little.

If lifestyle changes don’t work, you may be recommended a medicine like omeprazole.

Omeprazole and breastfeeding

Omeprazole is safe to take while you’re breastfeeding. It passes into breast milk, but only in small amounts which aren’t harmful to the baby.

However, if your baby is premature or has health problems, check with your doctor first.

Tell your doctor if you’re:

• trying to get pregnant
• pregnant
• breastfeeding

Cautions with other medicines

Some medicines and omeprazole can interfere with each other and make it more likely that you will have side effects.

Tell your doctor if you’re taking these medicines before you start omeprazole treatment:

• heart medicines such as cilostazol and digoxin
• anti-fungal medicines such as itraconazole, ketoconazole, posaconazole and voriconazole
• methotrexate (treats psoriasis and rheumatoid arthritis)
• HIV medicines
• phenytoin (an anti-epilepsy medicine)
• rifampicin (an antibiotic)
• blood thinning medicines, such as clopidogrel and warfarin

Mixing omeprazole with herbal remedies and supplements

• Do not take the herbal remedy for depression, St John’s wort, at the same time as omeprazole. St John’s wort may stop omeprazole working as well as it should.

Important

Tell your pharmacist or doctor if you’re taking other medicines including herbal remedies, vitamins or supplements.

Omeprazole uses

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.

Omeprazole 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.

Omeprazole dosage

Maintenance of healing of erosive esophagitis in Asian patients: 10 mg orally once a day

The usual omeprazole dose to treat:

• indigestion is 10mg to 20mg a day
• acid reflux disease is 20mg to 40mg a day
• stomach ulcers is 20mg to 40mg a day
• Zollinger-Ellison syndrome is 20mg to 120mg a day

Doses are usually lower for children and people with liver problems.

Omeprazole tablets and capsules

Each tablet or capsule contains 10mg, 20mg or 40mg of omeprazole.

Swallow tablets and capsules whole with a glass of water or juice.

If you have problems swallowing capsules, you can open some brands of omeprazole capsules and mix the granules inside with a small amount of water or fruit juice, or sprinkle them onto soft food, such as yogurt or apple puree.

Don’t open capsules that have a special coating (like those made by Dexel). Talk to your pharmacist if you’re not sure whether you can open your capsules.

Omeprazole also comes as a tablet that melts in your mouth.

You can buy omeprazole 10mg tablets and capsules from pharmacies. They’re the same as omeprazole 10mg tablets and capsules that you get on prescription, but they’re meant to be taken only by adults and only for up to 4 weeks.

Liquid omeprazole

Liquid omeprazole can be prescribed by a doctor and made to order for children and people who cannot swallow capsules or tablets. It will come with a syringe or spoon to help you take the right amount. If you don’t have a syringe or spoon, ask your pharmacist for one.

Adult Dose for Duodenal Ulcer

• Use: Short-term treatment of active 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.

Adult Dose for Helicobacter pylori Infection

• 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)
  • Triple therapy: 20 mg orally 2 times a day, taken concomitantly with amoxicillin and clarithromycin. Duration of therapy: 10 days
    
• DUAL THERAPY: Treatment of patients with H pylori infection and duodenal ulcer disease
  • Dual therapy: 40 mg orally once a day, taken concomitantly with clarithromycin. Duration of therapy: 14 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.

Adult Dose for Gastric Ulcer

• Use: Short-term treatment of active benign gastric ulcer
• 40 mg orally once a day. Duration of therapy: 4 to 8 weeks

Adult Dose for Erosive Esophagitis

Uses:

• Treatment of erosive esophagitis due to acid-mediated GERD
• Maintenance of healing of erosive esophagitis due to acid-mediated GERD

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 or gastroesophageal reflux disease (GERD) symptoms, an additional 4 to 8 week course of treatment should be considered.

Adult Dose for Multiple Endocrine Adenomas

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

Adult Dose for Systemic Mastocytosis

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

Adult Dose for Zollinger-Ellison Syndrome

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

Adult Dose for Hypersecretory Conditions

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

Adult Dose for Gastroesophageal Reflux Disease (GERD)

• Use: Treatment of symptomatic GERD
• 20 mg orally once a day. Duration of therapy: Up to 4 weeks

Adult Dose for Dyspepsia

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

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.

Pediatric Dose for Gastroesophageal Reflux Disease

• Use: Treatment of symptomatic GERD (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

Pediatric Dose for Erosive Esophagitis

Uses:

• Treatment of erosive esophagitis due to acid-mediated GERD
• Maintenance of healing of erosive esophagitis due to acid-mediated GERD

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 erosive esophagitis 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.

Renal Dose Adjustments

• No adjustment recommended.

Liver Dose Adjustments

• Combination therapy with clarithromycin: Avoid use
• Maintenance of healing of erosive esophagitis: 10 mg orally once a day

What should I do if I forget a dose?

• If you usually take it once a day, take the missed dose as soon as you remember, unless it’s within 12 hours of your next dose in which case skip the missed dose.
• If you usually take it twice a day, take the missed dose as soon as you remember, unless it’s within 4 hours of your next dose in which case skip the missed dose.

Do not take a double dose to make up for a forgotten dose.

If you forget doses often, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to help you remember to take your medicine.

What if I take too much?

Taking too much omeprazole by accident may cause side effects such as:

• feeling dizzy or sleepy
• seeing double
• slurring your words
• diarrhea
• passing out

Call your doctor or go to emergency department at a hospital straight away if you take too much omeprazole and have any side effects.

If you go to hospital, take the omeprazole packet or leaflet inside it plus any remaining medicines with you.

Omeprazole side effects

Most people who take omeprazole don’t have any side effects. If you do get a side effect, it’s usually mild and will go away when you stop taking omeprazole.

Common side effects

Common side effects, which happen in more than 1 in 100 people, include:

• headaches
• diarrhea
• stomach pain
• constipation
• wind
• feeling sick or vomiting

Omeprazole may also make you feel dizzy or sleepy. Some people might find it difficult to fall asleep.

It may also cause an itchy or lumpy skin rash or make your feet or ankles swell.

Talk to your doctor or pharmacist if the side effects bother you or don’t go away.

Serious side effects

Serious side effects are rare and happen in less than 1 in 1,000 people.

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

• rash
• hives
• itching
• swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
• difficulty breathing or swallowing
• hoarseness
• irregular, fast, or pounding heartbeat
• excessive tiredness
• dizziness
• lightheadedness
• muscle spasms
• uncontrollable shaking of a part of the body
• seizures
• diarrhea with watery stools
• stomach pain
• fever

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. The risk is highest in people who take high doses of one of these medications or take them for one year or longer.

Some people who take omeprazole for a long time may develop weakening of the stomach lining.

Tell a doctor straight away if you have:

• joint pain along with a red skin rash, especially in parts of your body exposed to the sun, such as your arms, cheeks and nose – these can be signs of a rare condition called subacute cutaneous lupus erythematosus that can happen weeks or even years after taking omeprazole
• yellow skin, dark pee and tiredness – these can be signs of liver problems
• reddening, blisters and peeling of the skin, there may also be severe blisters and bleeding in the lips, eyes, mouth, nose and genitals – these can be signs of Stevens-Johnson syndrome

Talk to your doctor about the risks of taking omeprazole.

Serious allergic reaction

In rare cases, it’s possible to have a serious allergic reaction (anaphylaxis) to omeprazole.

Contact a doctor straight away if:

• you get a skin rash that may include itchy, red, swollen, blistered or peeling skin
• you’re wheezing
• you get tightness in the chest or throat
• you have trouble breathing or talking
• your mouth, face, lips, tongue or throat start swelling

These are warning signs of a serious allergic reaction. A serious allergic reaction is an emergency.

These are not all the side effects of omeprazole. For a full list see the leaflet inside your medicines packet.

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