1. About carbocisteine
Carbocisteine is a type of medicine called a mucolytic.
A mucolytic helps you cough up phlegm (also called mucus or sputum). It works by making your phlegm less thick and sticky.
This can help if you have a condition that affects your lungs, including:
Carbocisteine is available on prescription only.
It comes as capsules and as a syrup or a liquid that you drink.
2. Key facts
- Carbocisteine can be taken by adults and children from the age of 2 years.
- You usually take this medicine 3 or 4 times a day.
- You can take it with or without food.
- Most people have no side effects when taking this medicine.
- Carbocisteine is known by the brand name Mucodyne.
3. Who can and cannot take carbocisteine
Carbocisteine can be taken by adults and by children aged 2 years and older.
Carbocisteine is not suitable for some people. Tell your doctor before taking this medicine if you:
- have had an allergic reaction to carbocisteine or any other medicines in the past
- have a stomach ulcer, or you've had stomach ulcers before
- are pregnant, planning to get pregnant, or are breastfeeding
4. How and when to take it
Carbocisteine usually comes as capsules.
It also comes as a liquid and as a syrup for children and people who find it difficult to swallow pills.
The liquid comes in individual sachets containing one dose. This is for adults and for children aged 15 and older.
The syrup comes with a plastic syringe or spoon to help you measure out the right dose. Do not use a kitchen spoon as this will not give you the correct amount.
You can take carbocisteine with or without food.
Dosage for adults
Capsules: two 375mg capsules, taken 3 times a day. When your symptoms improve, your doctor may recommend one 375mg capsule, taken 4 times a day.
Syrup: 15ml, taken 3 times a day. When your symptoms improve, your doctor may recommend 10ml, taken 3 times a day.
Liquid: 1 sachet, taken 3 times a day, reduced when symptoms improve to 1 sachet taken twice a day.
Dosage for children
2 to 4 years: 1.25ml to 2.5ml of syrup, given 4 times a day
5 to 11 years: 5ml of syrup, given 3 times a day
12 to 17 years: 15ml of syrup, given 3 times a day
What if I forget to take it?
If you forget a dose, take it as soon as you remember. If your next dose is due in less than 2 hours, skip the missed dose and take your next one as normal.
Never take 2 doses at the same time. Never take an extra dose to make up for a forgotten one.
If you forget doses often, it may help to set an alarm to remind you. You could also ask a pharmacist for advice on other ways to help you remember to take your medicine.
What if I take too much?
Taking too much carbocisteine is unlikely to harm you or your child. In most cases you will not have any symptoms.
If you need to go to A&E, do not drive yourself. Get someone else to drive you or call for an ambulance.
Take the carbocisteine packet, or the leaflet inside it, plus any remaining medicine with you.
5. Side effects
Like all medicines, carbocisteine can cause side effects, although not everyone gets them.
Common side effects
If you're taking carbocisteine capsules or liquid you're unlikely to have side effects.
However, with the carbocisteine sachets, common side effects can happen to 1 in 10 people. Tell your doctor if these bother you or do not go away:
- feeling or being sick
Serious side effects
Serious side effects are rare.
Serious allergic reaction
In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to carbocisteine.
These are not all the side effects of carbocisteine. For a full list see the leaflet inside your medicine packet.
6. How to cope with side effects
What to do about:
- diarrhoea – drink lots of fluids, such as water or squash, to avoid dehydration. Signs of dehydration include peeing less than usual or having dark, strong-smelling pee. Do not take any other medicines to treat diarrhoea without speaking to a pharmacist or doctor. If this continues, speak to your doctor. They may recommend taking syrup or capsules instead of sachets.
- feeling or being sick – stick to simple meals and do not eat rich or spicy food. It might help to take your medicine after you've eaten. If you're being sick, try small, frequent sips of water to avoid dehydration. Signs of dehydration include peeing less than usual or having dark, strong-smelling pee. If this continues, speak to your doctor. They may recommend taking syrup or capsules instead of sachets.
If you are still being sick after more than a few days, or if your vomit contains blood, stop taking the medicine and see your doctor.
7. Pregnancy and breastfeeding
Carbocisteine is not generally recommended when pregnant. This is because there is very little information to say whether it is safe. Depending on why you need a mucolytic, your doctor might recommend an alternative medicine.
Carbocisteine and breastfeeding
It is generally OK to take carbocisteine while breastfeeding, as the amount that passes into breast milk is unlikely to harm your baby.
8. Cautions with other medicines
Carbocisteine does not mix well with some medicines.
Tell your doctor or a pharmacist it you're taking any medicines that can cause bleeding or ulcers in your stomach. These include:
- NSAIDs (non-steroidal anti-inflammatory drugs) such as ibuprofen, naproxen or diclofenac and high-dose aspirin
- steroids (also called corticosteroids)
- clopidogrel or ticagrelor (antiplatelet medicines, sometimes called "blood thinners")
Mixing carbocisteine with herbal medicines
There is very little information about taking carbocisteine with herbal remedies and vitamin or mineral supplements. Not enough research has been done to say whether it is safe.
9. Common questions
How does it work?
How long does it take to work?
How long will I take it for?
Is it safe to take long term?
Are there similar medicines to carbocisteine?
Can I drink alcohol with it?
Are there foods and drinks I need to avoid?
Will it affect my contraception?
Will it affect my fertility?
Can I drive or ride a bike?
Page last reviewed: 06/01/2020
Next review due: 06/01/2023