Carbocisteine

What is carbocisteine?

Carbocisteine is a mucolytic medicine that helps reduce the thickness and stickiness of mucus (phlegm) in the lungs and airways. This makes it easier to cough up and helps improve breathing[1]. 

What is carbocisteine used to treat?

Carbocisteine is commonly prescribed for[1]: 

• Chronic Obstructive Pulmonary Disease (COPD) 

• Cystic fibrosis 

• Chronic bronchitis 

• Other conditions where thick mucus causes breathing problems 

How does carbocisteine work?

Carbocisteine works by breaking down mucus structure in the airways, making it less sticky and easier to clear when you cough. This helps prevent mucus buildup and lowers the risk of respiratory infections[1]. 

Who can take carbocisteine?

Carbocisteine is suitable for most adults and children over 2 years old, but it may not be appropriate for[1]: 

• People with a known allergy to carbocisteine 

• Anyone with current or past stomach ulcers 

• Those who are pregnant or breastfeeding – only take under medical supervision 

• Individuals who are lactose intolerant, as some formulations may contain lactose 

Please tell your doctor or pharmacist about any conditions you may have or medication you take before you start treatment, and always follow the instructions in the Patient Information Leaflet[2].  

What is the usual dose of carbocisteine?

The dose depends on your age, condition, and the form you’re using. Carbocisteine usually comes as capsules, but can also come in liquid or syrup form for children or people who find it difficult to swallow pills. Some solutions are adult-only due to alcohol content. The standard dose is:[1] 

• Adults (capsules): 375mg – take 2 capsules three times a day, reducing to 1 capsule three times a day as symptoms improve 

• Syrup (often for children): 15ml, 3 times a day for adults, reducing 10ml, but for children the dose varies based on age and weight – follow your doctor’s instructions 

• Liquid: 1 sachet, 3 times a day, or 15ml from a bottle, 3 times a day 

Always read the patient leaflet and take as directed by your doctor or pharmacist. 

How do you take carbocisteine?

There are different ways to take carbocisteine[1]: 

• Take with or after food to reduce stomach upset 

• Swallow capsules whole with water 

• Use a measuring spoon or oral syringe for liquid forms 

• Drink plenty of fluids throughout the day to help loosen mucus 

Can you stop taking carbocisteine?

You can usually stop taking carbocisteine once your symptoms improve – but speak to your doctor first. Stopping suddenly is safe for most people, but mucus may build up again if treatment ends too soon[1]. 

What if you take too much carbocisteine?

Too much carbocisteine can cause[1]: 

• Stomach pain 

• Nausea or vomiting 

• Diarrhoea 

If you take more than you should, contact your doctor or call NHS 111. Take the packaging with you if you need to go to A&E. 

What if you forget a dose of carbocisteine?

If you forget to take your dose[1]: 

• Take it as soon as you remember 

• If it's nearly time for your next dose, skip the missed one 

• Do not double up to make up for a forgotten dose 

Medicines to avoid with carbocisteine

Carbocisteine is generally safe to take with most other medicines. However, check with your doctor or pharmacist before combining it with[1]: 

• Antacids, which may reduce its effectiveness 

• Other mucolytics – to avoid duplicate treatment 

• NSAIDs or aspirin, especially if you have a history of stomach ulcers 

Always inform your doctor or pharmacist about all medications and supplements you take before you start a new medicine, and follow the instructions in the Patient Information Leaflet[2]. 

What are the side effects of carbocisteine?

Most people tolerate carbocisteine well, but the most common side effects can include[1]: 

• Diarrhoea 

• Nausea 

• Mild stomach discomfort 

Rare but serious side effects include[1]: 

• Allergic reactions (rash, swelling, breathing problems) 

• Bleeding in the stomach or intestines (look out for black stools or vomiting blood) 

You should contact your GP if you experience any of these symptoms. In rare cases, the medicine may cause a serious allergic reaction (anaphylaxis). You should call 999 or visit A&E immediately if you believe this is happening[1]. 

Symptoms of anaphylaxis include:  

• Difficulty breathing  

• Tightness in throat and chest  

• Swelling of the tongue or throat  

• Feeling faint or dizzy  

• Blue/grey skin or lips  

• Loss of consciousness

If you experience any side effects, including those not listed, you are encouraged to report them via the Yellow Card Scheme or contact your doctor, pharmacist, or nurse. This information is intended as a summary for general awareness and does not replace professional medical advice. 

The information provided in the side effects section is not a comprehensive list of all possible side effects associated with this medication. For a complete list of side effects, please refer to the Patient Information Leaflet (PIL) provided with your medication or consult your healthcare professional[2]. 

Frequently asked questions about carbocisteine

Is carbocisteine an antibiotic? 
No. Carbocisteine is a mucolytic, not an antibiotic. It helps clear mucus but doesn’t kill bacteria[1]. 

Can I drink alcohol while taking carbocisteine? 
Yes. There are no known interactions with alcohol, but drink in moderation[1]. 

How long does carbocisteine take to work? 
You may start to notice easier breathing within a few days, but it may take up to a week for full effect[1]. 

Can children take carbocisteine? 
Yes, but only under the supervision of a doctor and usually in syrup form[1]. 

For the official NHS guide for carbocisteine, visit their website.