A prodrug of the penicillin antibiotic ampicillin
Pivampicillin
An older penicillin antibiotic, taken by mouth, that turns into ampicillin in the body to treat infections.
What is Pivampicillin?
Pivampicillin is a penicillin antibiotic. It is a prodrug of ampicillin, meaning it is an inactive form that is absorbed well from the gut and then converted into ampicillin, the active antibiotic, inside the body. It is taken by mouth to treat bacterial infections. Because it is a penicillin, the most important safety point is the risk of an allergic reaction, so it must not be taken by anyone allergic to penicillins. It can cause stomach upset, and the pivoxil part of it can lower carnitine levels in the body, which matters with prolonged use, especially in children.
Education and reference only. This is a plain-language guide to Pivampicillin — 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
Pivampicillin is an antibiotic from the penicillin family. It is a prodrug of ampicillin: an inactive form that is absorbed more completely from the gut than ampicillin itself, then broken down inside the body to release the active antibiotic. This was designed to improve how much of the medicine reaches the bloodstream when taken by mouth. It is used to treat various bacterial infections, such as those affecting the chest, urinary tract or ears. It is an older medicine and is used much less commonly today.
How it works
Once swallowed, pivampicillin is absorbed and then converted in the body into ampicillin, the active antibiotic. Ampicillin, like other penicillins, works by stopping bacteria from building their cell walls properly, so the bacteria cannot survive and the infection clears. The prodrug design simply helps more of the medicine get absorbed when taken as tablets, so a useful amount reaches the bloodstream. The part of the molecule that makes this possible, called pivoxil, is released during conversion, and it is this part that is linked to lowering carnitine in the body.
Company & origin
Originated / developed by: Generic.
An older penicillin antibiotic, taken by mouth, designed to be absorbed better and then turned into ampicillin inside the body.
Practical use
How to take Pivampicillin
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it by mouth as prescribed, swallowing the tablets with water.
- Always tell your prescriber about any allergy to penicillins or other antibiotics before taking it.
- Finish the full course even if you feel better, so the infection is fully treated.
- Take it with or after food if it upsets your stomach, and report troublesome side effects.
- Avoid long or repeated courses unless advised, as the pivoxil part can lower carnitine over time.
Weighing it up
Advantages & disadvantages of Pivampicillin
Advantages
- Absorbed well from the gut, delivering ampicillin effectively when taken by mouth.
- Useful for a range of common bacterial infections.
- Part of the well-understood penicillin family with a long history of use.
Disadvantages
- Carries the penicillin risk of allergic reactions, which can rarely be severe.
- Can cause stomach upset such as nausea or diarrhoea.
- The pivoxil ester can lower carnitine with prolonged use, so long courses are avoided, especially in children.
Practical use
Good to know
As with any penicillin, the most important point with pivampicillin is allergy: anyone who has had a serious reaction to a penicillin must not take it, and any rash, swelling or difficulty breathing needs urgent attention. Like many antibiotics, it can cause stomach upset such as nausea or diarrhoea, and it is wise to finish the whole course so the infection is fully treated. A more specific point is that the pivoxil ester — the part that helps it be absorbed — can lower the body's level of carnitine, a substance used in energy metabolism. This is mainly a concern with prolonged or repeated courses, and particularly in young children, so long-term use is generally avoided. As always, antibiotics should be used only when truly needed to help limit resistance.
Who should not take it / use with caution
- People who have had a serious allergic reaction to penicillins must not take it.
- It is used with caution, and long-term use avoided, in young children because of the carnitine effect.
- It is used with care in people with carnitine-related problems or certain metabolic conditions.
Monitoring
- Watching for allergic reactions, especially early in treatment.
- Checking that the infection responds to treatment.
- Considering carnitine levels if long or repeated courses are needed.
Side effects
- Allergic reactions, ranging from rash to, rarely, severe whole-body reactions (anaphylaxis).
- Nausea, diarrhoea or other stomach upset, as with many antibiotics.
- Thrush or other effects from changes to the body's natural bacteria.
- With prolonged use, a fall in carnitine levels from the pivoxil ester.
Key interactions
- It may interact with other antibiotics and with some medicines such as methotrexate.
- Severe vomiting or diarrhoea (from any cause) can reduce absorption of the contraceptive pill; this is not a specific interaction with the antibiotic itself, but seek advice if you are unwell.
- Always tell your prescriber about all your medicines, including supplements.
Available as: Tablets taken by mouth.
Answers
Pivampicillin: frequently asked questions
What is pivampicillin?
It is a penicillin antibiotic, a prodrug of ampicillin, meaning it is absorbed well from the gut and then converted into the active antibiotic ampicillin inside the body to treat infections.
Why does penicillin allergy matter?
Pivampicillin is a penicillin, so anyone allergic to penicillins must not take it, because reactions can rarely be severe and life-threatening (anaphylaxis).
What is carnitine depletion?
The pivoxil part of the medicine, which helps it be absorbed, can lower the body's carnitine, a substance used in energy metabolism. This is mainly a concern with long or repeated courses, especially in children.
Should I finish the whole course?
Yes. Finish the full course even if you feel better, so the infection is fully treated and to help limit antibiotic resistance.
Can it upset my stomach?
Yes. Like many antibiotics, it can cause nausea or diarrhoea; taking it with or after food can help.
The wider class
About Penicillin antibiotic (ampicillin prodrug)
Pivampicillin belongs to the penicillin antibiotic (ampicillin prodrug) 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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