A carbapenem antibiotic given by injection for serious infections
Meropenem
A carbapenem antibiotic given by injection in hospital to treat serious bacterial infections.
What is Meropenem?
Meropenem is a carbapenem, a powerful type of antibiotic used in hospital to treat serious bacterial infections, including those that other antibiotics cannot clear. It is given into a vein. The main safety points are that it can cause an allergic reaction in people allergic to penicillin (the antibiotics are related), that carbapenems can rarely trigger seizures, and that, like other broad antibiotics, it can lead to a gut infection called C. difficile diarrhoea. It also lowers the levels of the epilepsy medicine valproate. It is used under specialist hospital supervision.
Education and reference only. This is a plain-language guide to Meropenem — 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
Meropenem is a broad-spectrum antibiotic from a group called carbapenems. It is a hospital medicine used to treat serious infections, such as those affecting the lungs, abdomen, urinary system, blood or the lining around the brain, and it is often kept for infections that are severe or caused by bacteria resistant to other antibiotics. Because it is given into a vein, it is used in hospital or under specialist arrangements. It works against a wide range of bacteria, which is why it is an important option for serious illness.
How it works
Meropenem kills bacteria by stopping them from building their cell walls, which they need to survive. Without a strong wall, the bacteria break apart and die. Carbapenems like meropenem work against a wide range of bacteria, including many that resist other antibiotics, which is why they are reserved for serious or difficult infections. Because it works against so many bacteria, it can also disturb the helpful bacteria in the gut, which is part of why broad antibiotics can sometimes lead to C. difficile diarrhoea.
Company & origin
Originated / developed by: Generic (long-established).
A hospital antibiotic used in the UK to treat serious or resistant bacterial infections, given into a vein.
Practical use
How to take Meropenem
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given into a vein by a healthcare professional, so follow the hospital team's plan.
- Tell the team about any allergy to penicillin or other antibiotics before treatment starts.
- Report any severe or watery diarrhoea during or after treatment, as it can signal a gut infection.
- If you take the epilepsy medicine valproate, make sure the team knows, as meropenem lowers its levels.
- Complete the full course as directed, even if you feel better, to clear the infection properly.
Weighing it up
Advantages & disadvantages of Meropenem
Advantages
- Works against a very wide range of bacteria, including many resistant ones.
- An important option for serious or life-threatening infections.
- Generally well tolerated when given and monitored in hospital.
Disadvantages
- Must be given into a vein, so it is a hospital or specialist treatment.
- Can cause an allergic reaction in people allergic to penicillin, as the antibiotics are related.
- Can rarely trigger seizures and, like other broad antibiotics, can lead to C. difficile diarrhoea.
Practical use
Good to know
An important safety point is that meropenem is related to penicillin, so people with a serious penicillin allergy can sometimes react to it, and any rash, swelling or breathing difficulty must be reported at once. Carbapenems can, rarely, trigger seizures, so the team is careful in people with epilepsy or kidney problems. Like other broad antibiotics, meropenem can upset the balance of gut bacteria and lead to C. difficile diarrhoea, so any severe or persistent diarrhoea during or after treatment should be reported promptly. A key drug interaction is that meropenem lowers the blood levels of the epilepsy medicine valproate, which can let seizures return, so this combination is usually avoided. It is given and monitored by the hospital team, who adjust treatment to the infection and to kidney function.
Who should not take it / use with caution
- People who have had a serious allergic reaction to meropenem or other carbapenems should not have it.
- It is used with great caution in people with a serious penicillin allergy, because the antibiotics are related.
- It is used with care in people with epilepsy or kidney problems, with the dose adjusted to kidney function.
Monitoring
- Watching how the infection responds, sometimes guided by blood tests and cultures.
- Checking kidney function, as the dose is adjusted to it.
- Watching for allergic reactions, seizures and signs of C. difficile diarrhoea.
Side effects
- Diarrhoea, nausea or stomach upset, and reactions where the drip goes in.
- Allergic reactions, ranging from rash to, rarely, serious reactions needing urgent care.
- C. difficile diarrhoea, which can be severe and needs prompt attention.
- Rarely, seizures, especially in people with epilepsy or kidney problems.
Key interactions
- It lowers the blood levels of the epilepsy medicine valproate, so this combination is usually avoided.
- It can interact with the gout medicine probenecid, which affects how the body clears meropenem.
- Tell the team about all your medicines, as kidney function affects how meropenem is handled.
Available as: A powder made up into a solution for injection or infusion into a vein.
Answers
Meropenem: frequently asked questions
What is meropenem used for?
It is a carbapenem antibiotic used in hospital to treat serious bacterial infections, including those resistant to other antibiotics, given into a vein.
Can I have it if I am allergic to penicillin?
Meropenem is related to penicillin, so a serious penicillin allergy means it is used with great caution; always tell the team about any antibiotic allergy.
Why might I get diarrhoea?
Broad antibiotics can upset gut bacteria and lead to C. difficile diarrhoea, so report any severe or watery diarrhoea during or after treatment.
Does it interact with my epilepsy medicine?
Yes, it lowers the levels of valproate, which can let seizures return, so this combination is usually avoided; tell the team what you take.
Why is it given into a vein?
Meropenem is not absorbed well from the gut, so it is given into a vein in hospital to treat serious infections effectively.
The wider class
About Carbapenem antibiotic
Meropenem belongs to the carbapenem antibiotic class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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