1. About codeine
Codeine is a painkiller. It's used to treat pain, for example after an operation or an injury. It's also used for long-standing pain when everyday painkillers, such as paracetamol, ibuprofen and aspirin have not worked.
Codeine is also used to treat diarrhoea.
Codeine is available on prescription. It comes as tablets, a liquid to swallow and as an injection. Codeine injections are usually only given in hospital.
You can also buy codeine from a pharmacy as a syrup (linctus) to treat dry coughs.
3. Key facts
- Codeine works by stopping pain signals from travelling along the nerves to the brain.
- 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 becoming addicted.
- 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 years old. Only give codeine to children aged 12 to 18 years if everyday painkillers like paracetamol and ibuprofen haven't worked.
4. Who can and can't take codeine
Codeine can be taken by adults and children aged 12 years and older.
Codeine is not suitable for some people. Tell your doctor before starting the medicine if you have:
- had an allergic reaction to codeine or any other medicines in the past
- a lung problem
- a head injury
- adrenal gland problems
- an illness which causes seizures
- an addiction to alcohol
- an underactive thyroid gland
- kidney or liver problems
- an enlarged prostate
- low blood pressure
- myasthenia gravis (a rare illness that causes muscle weakness)
- symptoms of ulcerative colitis (a bowel condition)
Do not give codeine to children who are under 18 years old and have had their tonsils or adenoids removed because of a sleep problem called obstructive sleep apnoea.
Codeine is not generally recommended in pregnancy. Tell your doctor before taking codeine if you're trying to get pregnant, are already pregnant or if you are breastfeeding.
5. How and when to take it
Follow your doctor's instructions about how to use this medicine. This is particularly important because codeine can be addictive.
Take codeine with, or just after, a meal or snack so it's less likely to make you feel sick.
You can take codeine at any time of day but try to take it at the same times every day and space your doses evenly.
Different types of codeine
Codeine comes as:
- tablets - these contain 15mg, 30mg or 60mg of codeine
- a liquid that you swallow - this contains 25mg of codeine in a 5ml spoonful
- cough syrup - this contains 15mg of codeine in a 5ml spoonful
- an injection (usually given in hospital)
If you're taking codeine as a liquid, it will come with a plastic spoon or syringe to help you measure the correct amount. Ask your pharmacist for one if you don't have it. Do not measure the liquid with a kitchen teaspoon because it won't give the right amount.
The usual dose of codeine is 15mg to 60mg.
The usual dose for treating pain:
- adults usually take one or two 30mg tablets every 4 hours, up to a maximum of 8 tablets (240mg) in 24 hours
- children (aged 12 to 17 years) usually take one or two 30mg tablets (or one or two 5ml spoonfuls of liquid) every 6 hours
- elderly people or people with kidney or liver problems usually take a 15mg tablet every 4 hours
The usual dose for treating diarrhoea:
- adults usually take one or two 30mg tablets (or one or two 5ml spoonfuls of liquid)
- children (aged 12 to 17 years) usually take one or two 30mg tablets (or one or two 5ml spoonfuls of liquid)
- elderly people or people with kidney or liver problems usually take a 15mg tablet
You can take this dose 3 or 4 times a day.
The usual dose for treating a cough:
- adults and children usually take one or two 5ml spoonfuls of cough syrup 3 or 4 times a day.
It's important not to take more than your prescribed dose.
Do not take more than 4 doses of codeine in 24 hours if you're:
- a child (aged 12 to 17 years)
- taking a 60mg dose
If you get side effects your dose may go down.
If your symptoms don't go away, your dose might go up or you may be prescribed a different medicine.
Talk to your doctor if your pain or diarrhoea isn't relieved by the dose of codeine prescribed for you, or if side effects bother you or don't go away.
How long will I take it for?
You might only need to take codeine for a few days.
Sometimes, you may need to take codeine for longer. But usually a different medicine will be prescribed for long term pain or diarrhoea, especially if you have side effects like constipation.
What if I forget to take it?
If you forget to take a dose, check the information on the patient information leaflet inside the packaging or ask your pharmacist or doctor for advice on what to do.
Never take 2 doses at the same time to make up for a forgotten one.
If you often forget doses, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to remember your medicine.
What will happen if I stop taking it?
If you need to take codeine for a long time your body can become tolerant to it.
This isn't usually a problem but you could get unpleasant withdrawal symptoms if you stop taking it suddenly.
If you want to stop taking codeine, talk to your doctor first. Your dose can be reduced gradually so you don't get unpleasant withdrawal symptoms.
If you stop taking it suddenly it can cause unpleasant withdrawal symptoms such as:
- feeling agitated
- feeling anxious
If you have been taking codeine for more than a few weeks do not stop taking it without speaking to your doctor first.
It's important not to take more than your prescribed dose, even if you think it's not enough to relieve your pain. Speak to your doctor first, if you think you need a different dose.
Taking too much codeine can be dangerous.
If you've taken an accidental overdose you may feel very sleepy, sick or dizzy. You may also find it difficult to breathe. In serious cases you can become unconscious and may need emergency treatment in hospital.
The amount of codeine that can lead to an overdose varies from person to person.
If you go to A&E, do not drive yourself - get someone else to drive you or call for an ambulance.
Take the codeine box or leaflet inside the packet plus any remaining medicine with you.
If you've been prescribed codeine, it's particularly important that you:
- store it properly and safely at home
- keep it out of the sight and reach of children
- never give your medicine to anyone else
Return any unused codeine to your pharmacist. They will dispose of it.
6. Taking codeine with other painkillers
Do not take painkillers that you buy with codeine in alongside prescribed codeine. You'll be more likely to get side effects.
7. Side effects
Like all medicines, codeine can cause side effects in some people - but many people have no side effects or only minor ones.
The higher the dose of codeine the more chance that you will get side effects.
Common side effects
Common side effects happen in more than 1 in 100 people. Talk to your doctor or pharmacist if the side effects bother you or don't go away:
- feeling or being sick (nausea or vomiting)
- feeling sleepy
- confusion, feeling dizzy and vertigo (a sensation of spinning)
- dry mouth
Serious side effects
Serious side effects happen in less than 1 in 100 people. Call a doctor straight away if you:
- have breathing difficulty or short shallow breathing
- have muscle stiffness
- get symptoms of low blood pressure which include feeling dizzy and tired
Call 999 or go to A&E straight away if you have a fit or seizure.
Serious allergic reaction
In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to codeine.
These are not all the side effects of codeine. For a full list see the leaflet inside your medicine packet.
8. How to cope with side effects
What to do about:
- constipation - try to get more fibre into your diet such as fresh fruit and vegetables and cereals. Try to drink several glasses of water or other non-alcoholic liquid each day. If you can, it may also help to do some gentle exercise. It's safe to use a laxative if your constipation doesn't go away. Usually, lactulose is best but check with a pharmacist or doctor first.
- feeling or being sick (nausea or vomiting) - take codeine with or just after a meal or snack to ease feelings of sickness. If you're being sick, try small frequent sips of water. This side effect should normally wear off after a few days. Talk to your doctor about taking an anti-sickness medicine if it carries on for longer.
- feeling sleepy - this side effect should go away within a few days as your body gets used to codeine. Talk to your doctor if it carries on for longer.
- confusion, feeling dizzy and vertigo - if codeine makes you feel dizzy when you stand up, try getting up very slowly or stay sitting down until you feel better. If you begin to feel dizzy, lie down so that you don't faint, then sit until you feel better. This side effect should wear off within a few days as your body gets used to codeine. Talk to your doctor if it carries on for longer.
- dry mouth - try chewing sugar-free gum or sucking sugar-free sweets. Your doctor can also prescribe an artificial saliva substitute to keep your mouth moist. This comes as a spray, gel or lozenge.
- headaches - it's safe to take an everyday painkiller such as paracetamol or ibuprofen. Talk to your doctor if the headaches get worse or last longer than a week.
9. Pregnancy and breastfeeding
Codeine isn't recommended during pregnancy and while breastfeeding.
In early pregnancy, it's been linked to problems in the unborn baby. If you take codeine at the end of pregnancy there's a risk that your newborn baby may get withdrawal symptoms or be born addicted to codeine.
However, it's important to treat pain in pregnancy. For some pregnant women with severe pain, codeine might be the best option. Your doctor is the best person to help you decide what's right for you and your baby.
For more information about how codeine can affect you and your baby during pregnancy, visit the Best Use of Medicines in Pregnancy (BUMPS) website.
Codeine and breastfeeding
Codeine isn't usually recommended if you're breastfeeding. Small amounts of codeine pass into breast milk and can cause breathing problems in the baby. Speak to your doctor as they may be able to recommend a different painkiller.
10. Cautions with other medicines
Some medicines and codeine interfere with each other and increase the chances of you having side effects.
Tell your doctor if you're taking any medicines:
- to help you sleep
- for depression - some types can't be taken with codeine
- for high blood pressure
- to help stop you feeling or being sick
- to treat symptoms of an allergy
- to reduce tension or anxiety
- for mental health problems
Mixing codeine with herbal remedies and supplements
It's not possible to say that complementary medicines and herbal remedies are safe to take with codeine. They're not tested in the same way as pharmacy and prescription medicines. They're generally not tested for the effect they have on other medicines.
11. Common questions
How does codeine work?
How long will it take to work?
Can I become addicted to codeine?
How will I know if I'm addicted to it?
Can I drink alcohol with it?
Is there any food or drink I need to avoid?
Can children take codeine?
Will it affect my fertility?
Are there other painkillers I can try?
Is codeine a controlled medicine?
Will it make me so sleepy I can't function?
Can I drive or ride a bike?
Will it affect my contraception?
Will recreational drugs affect it?
Page last reviewed: 27/11/2018
Next review due: 27/11/2021