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Colistimethate sodium for infection

Colobreathe, Colomycin, Promixin

Colistimethate sodium is an antibiotic. It is breathed into the lungs to treat chest infections in people with cystic fibrosis.

Your doctor or nurse will show you how to use it and give you the first few doses. If you are unsure about anything, ask for further advice.

Continue reading below

About colistimethate sodium

Type of medicine

Polymyxin antibiotic

Used for

Chest infections in people with cystic fibrosis

Infections caused by organisms which other antibiotics are not able to treat

Also called

Colomycin®; Promixin®; Colobreathe®

(It was previously called colistin sulfomethate sodium)

Available as

Capsules and powder for inhalation, and injection

Colistimethate sodium is an antibiotic which is used to treat infections caused by certain types of germs (bacteria). It works by killing the bacteria causing the infection. It is not absorbed by the body if it is taken by mouth, so instead it is given by injection or breathed into the lungs (inhaled). It is inhaled when it is for an infection which affects the lungs only (such as in people with cystic fibrosis). It is given by injection for infections which affect the body generally.

The rest of this leaflet deals with colistimethate sodium when it is inhaled for chest infections in people with conditions such as cystic fibrosis.

In people with cystic fibrosis, the cells that line the airways make phlegm (mucus) that is thicker than normal. This is not cleared from the lungs easily, and can trap bacteria and lead to infection. A germ (bacterium) called Pseudomonas aeruginosa commonly lives in the thick mucus in the airways. To keep it from flaring up into repeated infections, colistimethate sodium is inhaled into the lungs by nebuliser or inhaler device.

Before using colistimethate sodium

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start using colistimethate sodium it is important that your doctor knows:

  • If you are pregnant, trying for a baby or breastfeeding.

  • If you have problems with the way your kidneys work.

  • If you have a condition causing muscle weakness, called myasthenia gravis.

  • If you have a rare inherited blood disorder called porphyria.

  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

  • If you have ever had an allergic reaction to a medicine.

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How to take colistimethate sodium

  • Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack. The manufacturer's leaflet will give you more information about the medicine and a full list of the side-effects which you may experience from using it.

  • Use colistimethate sodium exactly as your doctor tells you to. Your doctor or nurse will give you/your child the first few doses and show you what to do. Ask for further information if there is anything you are not sure about.

  • If you are using a nebuliser, you will be shown how to make up the solution and how to nebulise it. As a guide only, the usual dose nebulised by adults and children over 2 years of age is 1 to 2 million units (1-2 vials) two or three times daily. This dose may be increased from time to time when needed.

  • If you have been given Colobreathe® capsules with an inhaler device, use one capsule in the device twice daily, 12 hours apart.

    • Insert the capsule widest end first into the inhaler chamber.

    • Pierce the capsule gradually using a two-step process (your nurse/doctor will demonstrate this for you) and remember only to pierce each capsule once.

    • Place the mouthpiece between your lips and form a seal around it.

    • Breathe in slowly but deeply so that you hear the capsule spin inside the inhaler.

    • Hold your breath for around ten seconds, or as long as you feel able to.

  • Remember to rinse out your mouth with water after each dose of Colobreathe® to remove any medicine that has deposited in your throat. This will reduce the risk of mouth infections and will help to remove the taste from the powder in the capsules.

  • Colobreathe® capsules must not be swallowed. They are not suitable for children under 6 years of age.

  • Try not to miss any doses. If you do forget a dose, have it as soon as you remember unless it is nearly time for your next dose, in which case leave out the missed dose. Do not have two doses together to make up for a forgotten dose.

Getting the most from your treatment

  • Try to keep your regular appointments with your doctor. This is so your doctor can check on your progress.

  • Your doctor may recommend another type of inhaler (a bronchodilator) to widen your airways as much as possible so that colistimethate can get deeper into your lungs. If this is the case, always use the inhaler before having a dose of colistimethate sodium.

  • All people with cystic fibrosis should be up to date with routine immunisations and have an annual flu jab to prevent influenza. It is also important to be immunised with pneumococcal vaccine to help prevent pneumonia caused by this bacterium.

  • It is important for people with cystic fibrosis to exercise and to be as active and fit as possible. So, sports and games such as running, swimming, football and tennis are encouraged.

  • If you are having an operation or dental treatment, tell the person carrying out the treatment that you are having this medicine. This is because colistimethate sodium can interfere with some anaesthetics and they may not be suitable for you.

  • If you buy any medicines, check with a pharmacist that they are suitable to take with your other medicines.

Continue reading below

Can colistimethate sodium cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with inhaled colistimethate sodium. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.

Common colistimethate sodium side-effects - these can affect more than 1 in 10 people who use this medicine


What can I do if I experience this?

Coughing and chest tightness

If you have been given a medicine to widen your airways (a bronchodilator), remember to use it before you use colistimethate sodium. Let your doctor know if this problem continues

Unpleasant taste, voice changes

After each dose, remember to rinse your mouth with water, then spit the water out

Sore mouth and sore throat

Let your doctor know about this

Feeling sick (nausea)

Let your doctor know if this continues

If you experience any other symptoms which you think may be due to this medicine, discuss them with your doctor or pharmacist.

How to store colistimethate sodium

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

Important information about all medicines

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

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