Omeprazole

About omeprazole

Omeprazole reduces the amount of acid your stomach makes. It's a widely-used treatment for indigestion and acid reflux. It's also taken to prevent and treat stomach ulcers.

Sometimes, omeprazole is taken for a rare illness caused by a tumour in the pancreas or gut called Zollinger-Ellison syndrome.

Omeprazole comes as capsules, tablets and as a liquid that you swallow (this is made to order).

All types of omeprazole are available on prescription. You can buy the lowest-strength 10mg tablets and capsules from pharmacies.

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 headache, 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 Losec and Losec MUPS.

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

How and when to take it

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.

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

How much should I take?

The usual 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.

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.

Will my 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.

How long will I take it 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.

What if I forget to take it?

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
diarrhoea
passing out

If this happens, call your doctor straight away, or go to the nearest hospital accident and emergency (A&E) department.

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

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
diarrhoea
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.

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

Serious allergic reaction

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

A serious allergic reaction is an emergency. Contact a doctor straight away if you think you or someone around you is having a serious allergic reaction.

The warning signs of a serious allergic reaction are:

getting a skin rash that may include itchy, red, swollen, blistered or peeling skin
wheezing
tightness in the chest or throat
having trouble breathing or talking
swelling of the mouth, face, lips, tongue, or throat

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

You can report any suspected side effect to the UK safety scheme.

How to cope with side effects

What to do about:

headaches - make sure you rest and drink plenty of fluids. Don’t drink too much alcohol. Ask your pharmacist to recommend a painkiller. Headaches should usually go away after the first week of taking omeprazole. Talk to your doctor if they last longer than a week or are severe.
feeling sick - try taking omeprazole with or after a meal or snack. It may also help if you don't eat rich or spicy food.
diarrhoea and vomiting - drink plenty of water in small, frequent sips. It may also help to take oral rehydration solutions. You can buy these from a pharmacy or supermarket to prevent dehydration. Do not take any other medicines to treat diarrhoea or vomiting without speaking to a pharmacist or doctor.
constipation - eat more high-fibre foods such as fresh fruit and vegetables and cereals, and drink plenty of water. Try to exercise more regularly, for example, by going for a daily walk or run. If this doesn't help, talk to your pharmacist or doctor.
wind - steer clear of foods that cause wind like pulses, lentils, beans and onions. It might also help to eat smaller and more frequent meals, eat and drink slowly, and exercise regularly. Some pharmacy remedies help with wind, such as charcoal tablets or simethicone.

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 pharmacist or doctor if you're trying to get pregnant, are already pregnant or if you're 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

Don't 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.

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

Common questions

How does omeprazole work?

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.

When will I feel better?

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.

Can I take paracetamol with it?

Yes, it’s safe to take paracetamol at the same time as omeprazole.

Are there similar medicines?

There are 4 other medicines that are similar to omeprazole. They are:

lansoprazole
esomeprazole
pantoprazole
rabeprazole

Like omeprazole, these medicines are proton pump inhibitors. They work in the same way as omeprazole to reduce acid in your stomach. They generally work as well as and have similar side effects to omeprazole. However, they may be given in different doses to omeprazole.

Sometimes, if omeprazole doesn't work or agree with you, your doctor may suggest that you try taking another proton pump inhibitor. Like omeprazole, you can buy esomeprazole and pantoprazole directly from pharmacies. You can also buy esomeprazole from supermarkets.

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.

Is omeprazole I buy 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.

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.

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.

Can I drink alcohol with it?

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 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