An injected antibiotic for serious Gram-positive infections
Daptomycin
A powerful antibiotic given by injection in hospital for serious bacterial infections, including those caused by MRSA.
What is Daptomycin?
Daptomycin is a powerful antibiotic given by injection or drip in hospital to treat serious infections caused by Gram-positive bacteria, including MRSA, such as some skin, blood and heart-valve infections. It works by attacking the outer membrane of these bacteria. An important point is that it must not be used for pneumonia, because it is switched off by a substance in the lung. Its main safety concern is muscle damage: it can raise a muscle enzyme (CK) and, occasionally, cause muscle pain or weakness, so this is monitored. Rarely it can cause a lung reaction called eosinophilic pneumonia.
Education and reference only. This is a plain-language guide to Daptomycin — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Daptomycin is an antibiotic used to treat serious infections caused by Gram-positive bacteria, including resistant ones such as MRSA. It is given by injection into a vein, in hospital, and is reserved for more serious infections such as certain skin and soft-tissue infections, bloodstream infections and infections of the heart valves. It belongs to a group called the lipopeptides and works in a distinctive way on the bacterial membrane. A key feature is that it cannot be used to treat pneumonia, because a natural substance in the lung stops it working. It is used under specialist guidance with regular monitoring.
How it works
Daptomycin works by attaching to the outer membrane of Gram-positive bacteria and disrupting it, which causes the bacteria to lose their internal balance and die. This action makes it effective against difficult bacteria, including MRSA. However, a natural lung substance (surfactant) binds to daptomycin and switches it off, which is why it does not work for pneumonia even though it is otherwise a strong antibiotic. Because it can affect muscle tissue, a muscle enzyme called creatine kinase is checked during treatment, and certain other medicines that affect muscle may be paused so problems can be picked up early.
Company & origin
Originated / developed by: Various manufacturers.
A hospital antibiotic given by injection or drip for serious infections, including those caused by MRSA, used under specialist guidance.
Practical use
How to take Daptomycin
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given by injection or drip by a healthcare professional, in hospital.
- Report any new muscle pain, tenderness or weakness during treatment.
- Report any new breathlessness, fever or cough, which can rarely signal a lung reaction.
- Tell the team about all medicines you take, especially statins, which may be paused.
- Make sure the team knows about any kidney problems, as the dose may need adjusting.
Weighing it up
Advantages & disadvantages of Daptomycin
Advantages
- Effective against serious Gram-positive infections, including MRSA.
- Useful for certain skin, bloodstream and heart-valve infections.
- Often given once a day, which can suit longer courses.
Disadvantages
- Given only by injection or drip, requiring hospital care.
- Cannot be used for pneumonia, because the lung inactivates it.
- Can damage muscle, needing regular blood tests, and rarely causes a lung reaction.
Practical use
Good to know
Two points stand out with daptomycin. First, it must not be used to treat pneumonia, because a substance in the lung inactivates it, so it would not work; this is an important prescribing rule. Second, its main safety concern is muscle damage: it can raise a muscle enzyme called creatine kinase and, occasionally, cause muscle aches, tenderness or weakness, so this enzyme is checked regularly and any unexplained muscle pain or weakness should be reported promptly. Where possible, other medicines that can also harm muscle, such as statins, may be paused during treatment. Rarely, it can cause a lung reaction called eosinophilic pneumonia, with new breathlessness, fever and cough, which needs urgent attention. It is a hospital antibiotic given by injection and is always managed by the medical team, with the dose adjusted for kidney function.
Who should not take it / use with caution
- People who have had a serious allergic reaction to daptomycin should not receive it.
- It is not used to treat pneumonia, because it is inactivated in the lung.
- It is used with caution alongside statins and other medicines that can affect muscle.
- The dose may need adjusting in people with reduced kidney function.
Monitoring
- Regular checks of the muscle enzyme creatine kinase, with attention to muscle symptoms.
- Watching for new breathlessness, fever or cough that could signal a lung reaction.
- Checking kidney function and adjusting the dose accordingly.
Side effects
- A rise in the muscle enzyme creatine kinase, sometimes with muscle aches or weakness.
- Reactions where the injection or drip is given.
- Nausea, diarrhoea or headache in some people.
- Rarely, a serious lung reaction (eosinophilic pneumonia) or serious allergic reactions.
Key interactions
- Statins and other medicines that can affect muscle may be paused during treatment.
- Tell the team about all medicines you take, including any that affect the kidneys.
- Other medicines affecting muscle can add to the risk, so the team reviews this.
Available as: A powder made up into a solution for injection into a vein.
Answers
Daptomycin: frequently asked questions
What is daptomycin used for?
It is a powerful antibiotic given by injection in hospital for serious Gram-positive infections, including MRSA, such as some skin, blood and heart-valve infections.
Why can't it be used for pneumonia?
A natural substance in the lung binds to daptomycin and switches it off, so it does not work for pneumonia and must not be used to treat it.
Why are my muscle blood tests checked?
Daptomycin can affect muscle and raise an enzyme called creatine kinase, so it is checked regularly and any unexplained muscle pain or weakness should be reported.
Why might my statin be paused?
Statins can also affect muscle, so they may be paused during treatment to make any muscle problems easier to spot.
What if I become breathless on it?
Rarely, daptomycin can cause a lung reaction with new breathlessness, fever and cough, which needs urgent attention, so report these symptoms promptly.
Authoritative sources
- BNF
- NICE CKS
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