A cephalosporin-type antibiotic given by injection
Cefoxitin
An injectable antibiotic used mainly to prevent infection around surgery and to treat infections in the abdomen and pelvis.
What is Cefoxitin?
Cefoxitin is a cephalosporin-type antibiotic, in a group called the cephamycins, given by injection in hospital. It is used to prevent infection around certain operations and to treat infections such as those in the abdomen and pelvis, because it works against a broad range of bacteria, including some that grow without oxygen. Because it is closely related to penicillins and other cephalosporins, it is used with care in people with allergies to those antibiotics. As with any antibiotic, it can disturb the gut and, in some people, lead to a serious bowel infection called Clostridioides difficile.
Education and reference only. This is a plain-language guide to Cefoxitin — 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
Cefoxitin is an antibiotic from the cephalosporin family, specifically a cephamycin, which covers a wide range of bacteria including some anaerobes that thrive where there is little oxygen, such as in the gut and pelvis. It is given by injection, usually into a vein, in a hospital setting. A common use is preventing wound infection around operations, particularly abdominal or pelvic surgery, and it is also used to treat established infections in those areas. It is prescribed and supervised by hospital teams rather than used at home.
How it works
Cefoxitin kills bacteria by stopping them from building their cell walls, so the bacteria fall apart and the infection is brought under control. As a cephamycin, it is fairly resistant to certain bacterial enzymes and works against a useful spread of organisms, including some that grow without oxygen, which makes it handy for gut and pelvic infections and for surgical prevention. Because it does not survive the digestive system well, it is given by injection rather than by mouth, which also lets it reach the bloodstream and tissues quickly.
Company & origin
Originated / developed by: Generic (hospital supply).
A hospital antibiotic used in the UK by injection, often to prevent infection around surgery or to treat infections in the abdomen and pelvis.
Practical use
How to take Cefoxitin
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given by injection, usually into a vein, by the hospital team, so there is nothing to take by mouth.
- Tell the team about any allergy to penicillins or cephalosporins before it is given.
- Report severe or watery diarrhoea during or after treatment, as this can signal a bowel infection.
- Complete the course the team prescribes, even if you start feeling better, to fully clear the infection.
- Mention any kidney problems, as these can affect how the dose is managed.
Weighing it up
Advantages & disadvantages of Cefoxitin
Advantages
- Works against a broad range of bacteria, including some that grow without oxygen.
- Useful for preventing infection around abdominal and pelvic surgery.
- Given by injection, so it reaches the bloodstream and tissues quickly.
Disadvantages
- Must be given by injection in hospital rather than taken at home.
- Can cause an allergic reaction, especially in people allergic to penicillins or cephalosporins.
- Like other antibiotics, can disturb the gut and rarely trigger a serious bowel infection.
Practical use
Good to know
The most important safety point is allergy: because cefoxitin is closely related to penicillins and other cephalosporins, anyone who has had a serious reaction to those antibiotics needs careful assessment before it is used. Like all antibiotics, it can upset the gut, and occasionally it disturbs the natural balance of bowel bacteria enough to allow a serious infection called Clostridioides difficile, so any severe or watery diarrhoea during or after treatment should be reported promptly. When used to prevent surgical infection it is usually given as a short course around the time of the operation rather than for long, to keep its use targeted. It is a hospital medicine, so it is given and monitored by the healthcare team, who will choose it based on the type of infection and local guidance.
Who should not take it / use with caution
- People who have had a serious allergic reaction to cefoxitin or other cephalosporins should not be given it.
- It is used with great caution in people with a serious penicillin allergy, because reactions can cross over between these antibiotics.
- It is used with care, and the dose adjusted, in people with kidney problems.
Monitoring
- Checking kidney function, especially with longer courses or existing kidney problems.
- Watching for signs of allergy or of a bowel infection such as severe diarrhoea.
- Reviewing how well the infection is responding to treatment.
Side effects
- Pain, redness or irritation where the injection is given.
- Diarrhoea, nausea or other gut upset.
- Allergic reactions, ranging from a rash to, rarely, a severe whole-body reaction.
- Rarely, a serious bowel infection (Clostridioides difficile) causing severe diarrhoea.
Key interactions
- It may add to the kidney effects of some other medicines, so the team reviews what you take.
- It can occasionally affect certain blood or urine test results, so labs should know it is being used.
- Tell the team about all your medicines, including any other antibiotics.
Available as: A powder made up into a solution for injection, usually into a vein.
Answers
Cefoxitin: frequently asked questions
What is cefoxitin used for?
It is an injectable antibiotic used mainly to prevent infection around operations, particularly abdominal or pelvic surgery, and to treat infections in those areas.
Can I take it as a tablet?
No. Cefoxitin does not survive the digestive system well, so it is given by injection, usually into a vein, in hospital.
I am allergic to penicillin - is it safe?
Cefoxitin is closely related to penicillins, so anyone with a serious penicillin allergy needs careful assessment, as reactions can cross over between these antibiotics.
Why might it cause diarrhoea?
Like all antibiotics it can disturb the gut, and occasionally this allows a serious bowel infection; report any severe or watery diarrhoea to your team.
How long is it given for?
For preventing surgical infection it is usually a short course around the time of the operation; for treating an infection the team decides the length.
The wider class
About Cephalosporin (cephamycin) antibiotic
Cefoxitin belongs to the cephalosporin (cephamycin) 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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