Omeprazole

Omeprazole is a type of medicine called a proton pump inhibitor (PPI). It works by reducing how much acid the stomach produces, which helps with problems linked to too much acid [1].

It is used for heartburn and acid reflux, gastro-oesophageal reflux disease (GORD), indigestion and stomach ulcers, and it can be part of treatment for a Helicobacter pylori infection [1]. It comes as tablets, capsules and a liquid, and lower-strength versions can be bought from a pharmacy [1].

• Omeprazole is usually taken once a day, and many people feel better within a few days [1].
• It is often taken in the morning, and can be taken with or without food [1].
• If you buy it from a pharmacy, do not take it for more than 2 weeks without seeing a doctor [1].
• Capsules and tablets should be swallowed whole and not crushed or chewed [1].

Most adults and children can take omeprazole, but it is not suitable for everyone [1]. It may not be right if you have had an allergic reaction to it or to other PPIs, or if you have liver problems or are due to have an endoscopy [1]. Tell a pharmacist or doctor about any health conditions before starting it, so they can check it is suitable [1].

Follow the instructions from your prescriber or on the pharmacy pack — the amount and timing depend on why you are taking it [1]. It is often taken at the same time each day, and if you take it once a day the morning is common [1]. If you find capsules hard to swallow, ask a pharmacist, as there are other ways to take it [1]. Do not stop a prescribed course without advice.

Common side effects can include headaches, feeling sick, wind, constipation or diarrhoea, and these are often mild [1]. Taking omeprazole for a long time may have other effects, which your doctor can discuss with you [1]. Get medical advice if side effects bother you or do not go away, and seek urgent help for signs of a serious reaction [1].

Omeprazole can interact with several medicines, including the heart medicine digoxin, the blood thinner clopidogrel, some HIV medicines, methotrexate and the herbal remedy St John's wort [1]. Tell a pharmacist or doctor what else you take, including anything bought over the counter, before starting it [1].

Suspected side effects from omeprazole can be reported to the MHRA through the Yellow Card scheme, which helps monitor medicine safety in the UK [2]. Seek medical help for any serious reaction as well as reporting it.