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About codeine

Codeine is a painkiller that is part of a group of medicines called opiates. It's used to treat pain, for example, after an operation or an injury. It's also used for ongoing pain when painkillers such as paracetamol, ibuprofen and aspirin have not worked. Codeine is also used to treat diarrhoea.

It works in the central nervous system and the brain to block pain signals to the rest of the body. It also reduces the anxiety and stress caused by pain.

Codeine is available on prescription and comes as tablets, a liquid you swallow and as an injection. Codeine injections are usually only given in hospital.

You can also buy lower-strength codeine from a pharmacy. It comes mixed with paracetamol (co-codamol) or with aspirin (co-codaprin) or with ibuprofen (Nurofen Plus).

Pharmacies also sell codeine as a syrup (linctus) to treat dry coughs.

Key facts

  • The most common side effects of codeine are constipation, feeling sick (nausea) and feeling sleepy.
  • It's possible to become addicted to codeine, but your doctor will explain how to reduce the risks of this happening.
  • If you need to take codeine for more than a few weeks, your treatment plan may include details of how and when to stop taking this medicine.
  • It may be best not to drink alcohol while taking codeine as you're more likely to get side effects like feeling sleepy.
  • Do not give codeine to children under 12. Only give codeine to children aged 12 to 18 if everyday painkillers, like paracetamol and ibuprofen, have not worked.

Page last reviewed: 31 January 2022
Next review due: 31 January 2025