A second-generation cephalosporin antibiotic
Cefamandole
An older injected cephalosporin antibiotic, notable for a disulfiram-like reaction with alcohol and a bleeding risk.
What is Cefamandole?
Cefamandole is an older second-generation cephalosporin antibiotic given by injection to treat bacterial infections. Like all cephalosporins it can cause allergic reactions, and people with a serious penicillin allergy may also react to it. It can upset the gut and, rarely, cause a serious bowel infection (Clostridioides difficile). Two features stand out because of its chemical structure: it can cause an unpleasant 'disulfiram-like' reaction if alcohol is drunk, with flushing and sickness, and it can increase the risk of bleeding. These drawbacks mean it is now little used in the UK.
Education and reference only. This is a plain-language guide to Cefamandole — 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
Cefamandole is a second-generation cephalosporin, a type of antibiotic related to penicillin, used to treat a range of bacterial infections. It was given by injection or infusion, usually in hospital. Its chemical structure includes a side chain (called NMTT) that gives it two characteristic problems: a reaction with alcohol and an effect on blood clotting. Because of these drawbacks, and the availability of newer cephalosporins without them, it is now little used in current UK practice, but it is a useful example of how an antibiotic's structure shapes its safety profile.
How it works
Like other cephalosporins, cefamandole kills bacteria by blocking their ability to build a strong cell wall, so the bacteria cannot survive. It is effective against a range of bacteria typical of the second-generation cephalosporins. The same molecule also contains a side chain that, separately from its antibiotic action, interferes with the way the body handles alcohol and with vitamin K, which is needed for normal blood clotting. This is why drinking alcohol can cause an unpleasant reaction and why the medicine can increase the risk of bleeding.
Company & origin
Originated / developed by: Various (largely historical).
An older second-generation cephalosporin antibiotic given by injection; it is now little used in the UK, partly because of its alcohol reaction and bleeding risk.
Practical use
How to take Cefamandole
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given by injection or infusion under medical supervision, not taken at home.
- Tell the team about any allergy to cephalosporins or penicillin before it is given.
- Do not drink alcohol during treatment or for a few days afterwards, as it can cause a flushing-and-sickness reaction.
- Report any unusual bruising or bleeding, as it can affect blood clotting.
- Tell the team about blood-thinning medicines, as the bleeding risk can add up.
Weighing it up
Advantages & disadvantages of Cefamandole
Advantages
- An effective second-generation cephalosporin against a range of bacterial infections.
- Works by the reliable cephalosporin action of attacking the bacterial cell wall.
- Given by injection, useful for infections needing hospital treatment.
Disadvantages
- Causes a disulfiram-like reaction with alcohol, with flushing and sickness.
- Can interfere with blood clotting and increase the risk of bleeding.
- Now little used in the UK, with newer cephalosporins preferred.
Practical use
Good to know
Three safety points matter most with cefamandole. First, as a cephalosporin it can cause allergic reactions, and there is a chance of cross-reaction in people with a serious penicillin allergy, so allergy history must be checked. Second, because of its NMTT side chain it can cause a disulfiram-like reaction with alcohol: drinking alcohol during treatment, and for a short time afterwards, can cause flushing, headache, a fast heartbeat and sickness, so alcohol should be avoided. Third, the same side chain can interfere with vitamin K and increase the risk of bleeding, particularly in people who are unwell, poorly nourished or also taking blood-thinning medicines, so bleeding signs are watched and vitamin K may be given. As with all antibiotics, it can upset the gut and, rarely, cause a serious bowel infection (Clostridioides difficile).
Who should not take it / use with caution
- People who have had a serious allergic reaction to a cephalosporin should not receive it.
- It is used with caution in people with a serious penicillin allergy, because of possible cross-reaction.
- It is used with caution in people with bleeding problems or poor nutrition, because of the bleeding risk.
- Alcohol should be avoided during and shortly after treatment.
Monitoring
- Checking for cephalosporin or penicillin allergy before it is given.
- Watching for bleeding or bruising, with blood clotting tests where needed.
- Checking the infection responds and watching for gut side effects.
Side effects
- Allergic reactions, from rashes to, rarely, severe reactions.
- A disulfiram-like reaction (flushing, headache, fast heartbeat, sickness) if alcohol is drunk.
- Bleeding or bruising from its effect on blood clotting.
- Diarrhoea or stomach upset and, rarely, a serious bowel infection (Clostridioides difficile).
Key interactions
- Alcohol can cause a disulfiram-like reaction, so it should be avoided during and shortly after treatment.
- Blood-thinning medicines such as warfarin can add to the bleeding risk.
- Tell the team about all your medicines and any antibiotic allergies.
Available as: A powder made up into a solution for injection or infusion.
Answers
Cefamandole: frequently asked questions
What is cefamandole used for?
It is an older second-generation cephalosporin antibiotic given by injection to treat bacterial infections; it is now little used in the UK.
Why must I avoid alcohol with it?
Its NMTT side chain can cause a disulfiram-like reaction, so drinking alcohol during or shortly after treatment can cause flushing, headache, a fast heartbeat and sickness.
Can people with penicillin allergy take it?
Cephalosporins can cross-react with penicillin, so anyone with a serious penicillin allergy should tell the team, and it is used with caution or avoided.
Does it affect bleeding?
Yes, it can interfere with vitamin K and blood clotting and increase the risk of bleeding, especially in people who are unwell or on blood thinners.
Why is it not used much now?
Newer cephalosporins without the alcohol reaction and bleeding risk are available, so cefamandole is now little used.
The wider class
About Cephalosporin antibiotic (second generation)
Cefamandole belongs to the cephalosporin antibiotic (second generation) 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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