A penicillin antibiotic for resistant Gram-negative infections
Temocillin
A penicillin antibiotic given into a vein for certain resistant Gram-negative infections.
What is Temocillin?
Temocillin is a penicillin-type antibiotic given into a vein in hospital, used mainly for infections caused by resistant Gram-negative bacteria, including some urinary and bloodstream infections. It is valued because it can work against bacteria that produce enzymes which break down many other penicillins. It is generally well tolerated, with side effects similar to other penicillins. Because it is a penicillin, it should not be used by people with a true penicillin allergy. Its spectrum is deliberately narrow, so it is chosen when the bacteria are known or strongly suspected to be suitable.
Education and reference only. This is a plain-language guide to Temocillin — 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
Temocillin is an antibiotic belonging to the penicillin family. It is given as an injection or infusion into a vein in hospital and is used mainly to treat infections caused by certain resistant Gram-negative bacteria, such as some urinary tract infections and bloodstream infections. Its particular value is that it stays effective against many bacteria that make enzymes (beta-lactamases) which destroy other penicillins. It has a deliberately narrow range of activity, so it is usually chosen with microbiology guidance once the likely bacteria are known.
How it works
Like other penicillins, temocillin kills bacteria by stopping them from building their cell walls, so the bacteria break apart and die. What sets it apart is its stability against many of the enzymes that resistant Gram-negative bacteria use to inactivate other penicillins, which lets it treat infections those medicines can no longer clear. Because it focuses on Gram-negative bacteria and does little against many other types, it is used in a targeted way rather than as a broad, everyday antibiotic. It is given into a vein so enough reaches the infection.
Company & origin
Originated / developed by: Specialist manufacturer.
A penicillin-type antibiotic used in hospital in the UK mainly for infections caused by resistant Gram-negative bacteria, such as some urinary and bloodstream infections.
Practical use
How to take Temocillin
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- It is given as an injection or infusion into a vein by hospital staff; you do not take it yourself.
- Tell the team before treatment if you have ever had an allergic reaction to penicillin or any antibiotic.
- Report any rash, itching, swelling or difficulty breathing straight away, as these can signal an allergy.
- Complete the full course the team prescribes, even if you feel better, so the infection is properly cleared.
- Mention any kidney problems, as the team may take these into account when planning treatment.
Weighing it up
Advantages & disadvantages of Temocillin
Advantages
- Stays effective against many resistant Gram-negative bacteria that destroy other penicillins.
- Generally well tolerated, with side effects similar to other penicillins.
- Its narrow, targeted action is less likely to disturb the body's wider balance of bacteria.
Disadvantages
- Cannot be used by people with a true penicillin allergy.
- Has a deliberately narrow range, so it does not cover many other types of bacteria.
- Is given into a vein in hospital rather than as a tablet at home.
Practical use
Good to know
A helpful thing to know about temocillin is that, although it is a penicillin, its action is deliberately narrow and aimed at resistant Gram-negative bacteria, so it is chosen for specific infections rather than as a general-purpose antibiotic; this narrow focus also means it is less likely to disturb the wider balance of bacteria in the body than some broad antibiotics. It is generally well tolerated, with side effects much like other penicillins, such as occasional stomach upset or reactions where the drip goes in. The most important safety point is allergy: because it is a penicillin, it must not be used by anyone who has had a true penicillin allergy, and any sign of an allergic reaction during treatment should be reported at once. It is given and monitored in hospital, usually with advice from the microbiology team.
Who should not take it / use with caution
- People who have had a true allergic reaction to penicillins should not be given it.
- It is used with care in people with kidney problems, who may need their treatment adjusted.
- It should be used under hospital supervision, usually with microbiology guidance, so it targets the right infection.
Monitoring
- Watching for allergic reactions, especially early in treatment.
- Reviewing how the infection responds and how long treatment is needed.
- Checking blood counts and kidney or liver function during longer courses where appropriate.
Side effects
- Reactions where the drip or injection goes in, such as soreness or redness.
- Stomach upset, such as nausea or diarrhoea, in some people.
- Allergic reactions, ranging from a rash to, rarely, a serious whole-body reaction needing urgent care.
- Rarely, changes in blood counts or liver blood tests, picked up by monitoring during longer treatment.
Key interactions
- Tell the team about all your medicines, although temocillin has relatively few major interactions.
- As with other penicillins, the medicine methotrexate may need extra care when given together.
- Your kidney function may affect dosing, so the team reviews this when planning treatment.
Available as: A powder made up into a solution for injection or infusion into a vein, given in hospital.
Answers
Temocillin: frequently asked questions
What is temocillin used for?
It is a penicillin antibiotic given into a vein for infections caused by resistant Gram-negative bacteria, such as some urinary and bloodstream infections.
Why is it used instead of other penicillins?
It stays effective against many bacteria that make enzymes which destroy other penicillins, so it can treat infections those medicines can no longer clear.
Can I have it if I am allergic to penicillin?
No. Temocillin is a penicillin, so it should not be used by anyone who has had a true penicillin allergy; tell the team about any antibiotic allergy.
Why is its range described as narrow?
It is aimed mainly at Gram-negative bacteria and does little against many other types, so it is chosen in a targeted way for specific infections.
Is it well tolerated?
Yes, it is generally well tolerated, with side effects similar to other penicillins, such as occasional stomach upset or reactions where the drip goes in.
The wider class
About Penicillin antibiotic (into a vein)
Temocillin belongs to the penicillin antibiotic (into a vein) 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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