Side Effects Of Omeprazole

NHS medicines information on some of the common and rare side effects of taking omeprazole.

Common side effects

These common side effects of omeprazole happen in more than 1 in 100 people. There are things you can do to help cope with them.

If this advice does not help and any of these side effects continue to bother you, tell your doctor or pharmacist.

Serious side effects

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

Call a doctor or call 111 straight away if:

• your skin becomes more yellow (although this may be less obvious on brown or black skin), your pee becomes darker and you feel more tired - these can be signs of liver problems
• you get joint pain along with a red skin rash, especially on 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. This can happen even if you have been taking omeprazole for a long time
• severe or persistent diarrhoea - this can be a sign of an inflamed bowel

Serious allergic reaction

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

Long-term side effects

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.

Omeprazole and stomach cancer

There is some research to suggest that taking medicines to reduce stomach acid, like PPIs and H2 blockers, may slightly increase the chance of developing stomach cancer. It also suggested that it could be more likely in people taking them for longer than 3 years. But studies involving more people need to be done to be sure that PPIs and H2 blockers cause stomach cancer, rather than something else causing it.

PPIs, like most medicines, have side effects so it's best to take them for the shortest time possible.

It's also important to speak to your doctor if you notice any of these symptoms which can be signs of stomach cancer:

• having problems swallowing (dysphagia)
• feeling or being sick
• feeling full very quickly when eating
• losing weight without trying

Speak to your doctor or pharmacist if you are concerned.

Other side effects

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

If you want to find out more about this particular topic you can visit the Original article on the NHS website. If you are worried by any aspect of your health make sure you go and see your doctor or book an appointment at your local clinic.