Omeprazole

NHS information about the medicine omeprazole, including what it's used for, who can take it, how to take it and side effects.

What omeprazole is for

Omeprazole is a medicine called a proton pump inhibitor (PPI). It reduces the amount of acid in your stomach.

It's used to treat or prevent conditions and symptoms such as:

• stomach ulcers
• heartburn
• gastro-oesophageal reflux disease (GORD)
• the stomach infection Helicobacter pylori (along with antibiotics)
• discomfort from severe reflux in children

How to take omeprazole

Omeprazole usually comes as tablets, capsules and liquid that you swallow. Some tablets can be dissolved in water.

How much to take and for how long depends on the type of omeprazole you're taking and why you're taking it.

It's usually taken once or twice a day. Some people may only need to take it for a few days, others may need to take it for several weeks, months or years.

Always check the packet or leaflet that comes with your medicine. Ask a pharmacist or doctor for advice if you're not sure how to take it or you have any problems taking it.

When taking omeprazole:

• try to take it at the same time each morning if you take it once a day, or at the same time each morning and evening if you take it twice a day
• you can take it with or without food
• swallow tablets and capsules with water – do not chew or crush capsules or tablets labelled "enteric coated" or "gastro resistant"

Ask a pharmacist for advice if you have problems swallowing pills or capsules. They may be able to suggest different ways to take your medicine.

• How to give different types of medicines (Medicines for Children website)

Side effects of omeprazole

Like all medicines, omeprazole can cause side effects, but not everyone gets them.

Common side effects

Common side effects of omeprazole include:

• a headache
• stomach pain
• feeling sick (nausea) or being sick (vomiting)
• constipation or diarrhoea
• farting more than usual

Omeprazole will not usually affect your ability to drive, ride a bike or use machinery. But if you feel dizzy or have problems with your vision after taking it, wait until you no longer have these side effects.

More about side effects

These are not all the side effects of omeprazole.

For a full list, see the leaflet that comes with your medicine or search for your medicine on the electronic medicines compendium website.

You can report any side effects you get on the Yellow Card website

Who can and cannot take omeprazole

Most adults and children can take omeprazole. But the tablets you can buy from pharmacies and shops without a prescription are only for adults over 18 years old.

Omeprazole is not suitable for some people. For example, it may not be suitable if:

• you've had an allergic reaction or serious side effect from omeprazole or another proton pump inhibitor (PPI) medicine that reduces stomach acid
• you have a kidney or liver condition
• you have osteoporosis (weakened bones)

Before taking omeprazole, tell your doctor or a pharmacist if you have any medical conditions.

Omeprazole can also affect the result of some tests, including blood tests, checks for some types of tumours and a test to check inside your food pipe (oesophagus) and stomach (gastroscopy).

If you're referred for a test, you may need to stop taking omeprazole for a few days or weeks before you have the test. Check with the staff at the hospital or clinic where the test is being done.

Breastfeeding and omeprazole

You can usually take omeprazole while breastfeeding, but check with a pharmacist or doctor first.

It's rare for breastfed babies to get any side effects from medicine you're taking, but speak to a healthcare professional if you have any concerns about your baby.

Pregnancy and omeprazole

You can usually take omeprazole if you're pregnant, but check with a pharmacist or doctor first.

Find out more about taking proton pump inhibitors, including omeprazole, during pregnancy on the Bumps (Best Use of Medicines in Pregnancy) website

Taking omeprazole with other medicines, food and drink

There are some medicines, remedies and supplements that may not mix well with omeprazole.

These include:

• other medicines that reduce stomach acid, such as lansoprazole and famotidine
• the heart medicine digoxin
• some medicines to prevent blood clots, such as warfarin and clopidogrel
• the sedative diazepam
• the anti-seizure medicine phenytoin
• the herbal remedy for low mood, St John's Wort
• HIV medicines called nelfinavir and atazanavir

Before you take omeprazole, tell your doctor or a pharmacist if you're taking any other medicines, herbal remedies, vitamins or supplements.

If you bought omeprazole without a prescription, check the packet or leaflet that comes with the medicine to see if it's suitable for you. Speak to a pharmacist or doctor if you're not sure if you can take it.

Food and alcohol with omeprazole

You can eat as normal while taking omeprazole, but it's best to not drink alcohol because it can increase the amount of acid in your stomach and make your symptoms worse.

Find out more about your medicine

To find out more about your medicine, you can:

• check the leaflet that comes with it
• search for your medicine leaflet on the electronic medicines compendium website
• find out about omeprazole for reflux in children on the Medicines for Children website
• speak to a pharmacist or doctor