Codeine

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 aspirin, ibuprofen and paracetamol, haven't 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 buy lower-strength codeine from a pharmacy. It comes mixed with paracetamol (co-codamol) or with aspirin (co-codaprin) or with ibuprofen (Nurofen Plus).

You can also buy codeine from a pharmacy as a syrup (linctus) to treat dry coughs.

2. 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 this is rare if you're taking it to relieve pain and your doctor is reviewing your treatment regularly.
  • 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.

3. Who can and can't take codeine

Codeine can be taken by adults and children aged 12 years and older.

Only give codeine to children (aged 12 to 18 years) if everyday painkillers such as paracetamol and ibuprofen haven't worked.

Codeine is not suitable for some people. Tell your doctor before starting the medicine if you have:

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.

4. How and when to take it

It's important to take codeine as your doctor has asked you to.

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.

How much to take

The usual dose of codeine is 15mg to 60mg. You can take this dose up to 4 times a day.

For treating pain:

  • adults usually take one or two 30mg tablets every 4 hours
  • children (aged 12 to 18 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

For treating diarrhoea:

  • adults usually take one or two 30mg tablets (or one or two 5ml spoonfuls of liquid) every 4 hours
  • children (aged 12 to 18 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

For treating a cough: Adults and children usually take one or two 5ml spoonfuls of cough syrup every 4 to 6 hours.

Important

Do not take more than 4 doses of codeine in 24 hours if you're:

  • a child (aged 12 to 18 years)
  • taking a 60mg dose

Will my dose go up or down?

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
  • shaking
  • sweating

Important

If you have been taking codeine for more than a few weeks do not stop taking it without speaking to your doctor first.

What if I take too much?

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've taken too much codeine by accident call your doctor or go to A&E straight away

If you go to a hospital accident and emergency (A&E) department, 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.

Storing codeine

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.

5. Taking codeine with other painkillers

It's safe to take codeine with paracetamol, ibuprofen or aspirin (aspirin is suitable for most people aged 16 years and over).

Some painkillers that you can buy without a prescription from pharmacies contain codeine. They include co-codamol, Nurofen Plus and Solpadeine.

Do not take codeine-containing painkillers that you can buy alongside prescribed codeine. You'll be more likely to get side effects.

6. 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:

  • constipation
  • feeling or being sick (nausea or vomiting)
  • feeling sleepy
  • confusion, feeling dizzy and vertigo (a sensation of spinning)
  • dry mouth
  • headaches

Serious side effects

Serious side effects happen in less than 1 in 100 people. Call a doctor straight away if you get:

  • breathing difficulty or short shallow breathing
  • muscle stiffness
  • symptoms of low blood pressure which include feeling dizzy and tired
  • (fits) seizures

If you have a fit go to A&E straight away.

Serious allergic reaction

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

Contact a doctor straight away if:

  • you get a skin rash that may include itchy, red, swollen, blistered or peeling skin
  • you're wheezing
  • you get tightness in the chest or throat
  • you have trouble breathing or talking
  • your mouth, face, lips, tongue or throat start swelling

These are warning signs of a serious allergic reaction. A serious allergic reaction is an emergency.

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

Information:

You can report any suspected side effect to the UK safety scheme.

7. 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.

8. 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.

Tell your doctor if you're:

  • trying to get pregnant
  • pregnant
  • breastfeeding

9. 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.

Important

Tell your doctor or pharmacist if you're taking any other medicines, including herbal remedies and supplements.

10. Common questions

How does codeine work?

Codeine is from a group of medicines called opiates, or narcotics.

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.

When codeine blocks the pain, there are other unwanted effects - for example slow or shallow breathing. It also slows down digestion, which is why codeine can cause constipation.

How long will it take to work?

This depends on the type of codeine you take.

A codeine injection into a vein gives the quickest pain relief. It works almost straight away.

Codeine tablets, liquid and cough syrup all work in 30 to 60 minutes, but they wear off after a few hours.

Can I become addicted to codeine?

Yes, codeine is addictive. But in reality, if you're taking it as a painkiller under medical supervision, it's very unlikely you will get addicted to it. People who take it as a recreational drug to get "high" are more likely to become addicted.

How will I know if I'm addicted to it?

If you're addicted to codeine, you may want to take it more often or feel agitated if you delay taking a dose for any reason.

And if you stop taking codeine suddenly you may suffer from withdrawal symptoms.

Talk to your doctor if you're worried about addiction.

Can I drink alcohol with it?

Drinking alcohol while you're on codeine may make you feel more sleepy or increase the risk of serious side effects.

It's best to stop drinking alcohol during the first few days of treatment until you see how codeine affects you.

If you feel sleepy with codeine, stop drinking alcohol while you're taking it.

Is there any food or drink I need to avoid?

You can eat and drink normally while taking codeine.

Can children take codeine?

Do not give codeine to babies and children under 12 years old.

Children aged 12 to 18 years can take codeine for pain or diarrhoea - but only if other medicines haven't worked. Use the lowest dose that works for no more than 3 days. If they still have symptoms after 3 days see a doctor.

Codeine shouldn't be given to children aged 12 to 18 years if they have breathing problems or if they have had their tonsils or adenoids removed because of obstructive sleep apnoea.

Will it affect my fertility?

If you're taking codeine for a short time and at normal doses, there's no firm evidence that it can reduce fertility.

However if you've been taking it for a long time and you're concerned about your fertility, or you're trying to get pregnant, speak to a pharmacist or your doctor.

Are there other painkillers I can try?

The type of painkiller that's best depends on what type of pain you have. If codeine doesn't get rid of your pain or becomes less effective, talk to your doctor.

Is codeine a controlled medicine?

Codeine is a controlled medicine. This means there are extra rules on how it's prescribed and dispensed to make sure it's not given to the wrong person or misused. However, this doesn't affect you as a patient. The rules only apply to the pharmacy that dispenses it.

Will it make me so sleepy I can't function?

When you first take codeine, you'll probably feel sleepy for a few days. But the sleepiness will wear off as your body gets used to the medicine.

You might notice you're less alert. In this case, you might choose to have less than perfect pain relief as a trade-off.

Can I drive or ride a bike?

Do not drive a car or ride a bike if codeine makes you sleepy during the daytime, gives you blurred vision or makes you feel dizzy, clumsy or unable to concentrate or make decisions. This may be more likely when you first start taking codeine but could happen at any time - for example when starting another medicine.

It's an offence to drive a car if your ability to drive safely is affected. It's your responsibility to decide if it's safe to drive. If you're in any doubt, do not drive.

Even if your ability to drive is not affected, the police have the right to request a saliva sample to check how much codeine is in your body. GOV.UK has more information on the law on drugs and driving.

Talk to your doctor or pharmacist if you're unsure whether it's safe for you to drive while taking codeine.

Will it affect my contraception?

Codeine doesn't affect any type of contraception, including the combined pill or emergency contraception

But, if you are taking codeine because you have severe diarrhoea (6 to 8 watery poos in 24 hours) your contraceptive pills may not protect you from pregnancy. Look on the pill packet to find out what to do.

Will recreational drugs affect it?

If you take recreational drugs, such as cannabis, cocaine and heroin while you're taking codeine, you're more likely to get the serious side effects of codeine including breathing difficulties, heart problems, seizures and even go into a coma.

Some recreational drugs, such as cannabis, will also increase codeine side effects such as sleepiness and dizziness.

Taking heroin while you're on prescribed codeine is especially dangerous. You're more likely to get all the side effects of codeine, including addiction.

Tell your doctor if you think you may take recreational drugs while you're on codeine.

Page last reviewed: 27/11/2018
Next review due: 27/11/2021