A macrolide antibiotic used in toxoplasmosis in pregnancy
Spiramycin
A macrolide antibiotic used especially in pregnancy to help stop toxoplasmosis being passed to the baby.
What is Spiramycin?
Spiramycin is a macrolide antibiotic used mainly to reduce the risk of toxoplasmosis, an infection caused by a parasite, being passed from a pregnant woman to her unborn baby. It is taken by mouth and is used because it builds up in the placenta, where it can help limit spread to the baby. The most common side effects are stomach upset, such as nausea and diarrhoea. Like some other macrolides it can affect the heart's rhythm (the QT interval) in some people. It is prescribed and supervised by a specialist.
Education and reference only. This is a plain-language guide to Spiramycin — 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
Spiramycin is an antibiotic in the macrolide family. Its main use in the UK is in pregnancy, where it is used to help reduce the chance of toxoplasmosis passing from the mother to the unborn baby. Toxoplasmosis is an infection caused by a parasite that is usually mild in the mother but can harm the baby if it crosses the placenta. Spiramycin is taken by mouth and is chosen because it concentrates in the placenta. It is a specialist medicine, prescribed and supervised by the team looking after the pregnancy.
How it works
Spiramycin works like other macrolide antibiotics by stopping bacteria and certain other organisms from making the proteins they need to grow and multiply. In toxoplasmosis in pregnancy, it builds up in the placenta, where it is thought to limit the spread of the parasite from mother to baby. Because it concentrates there, it is used to reduce the chance of the infection reaching the baby, particularly when the infection is caught early in pregnancy. The specialist team decides how and for how long it is used, depending on the situation.
Company & origin
Originated / developed by: Specialist manufacturer.
A macrolide antibiotic used in the UK mainly to reduce the chance of toxoplasmosis passing from mother to baby in pregnancy.
Practical use
How to take Spiramycin
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Take it by mouth exactly as your specialist team advises, completing the full course.
- Taking it with water and spacing doses as instructed can help; tell your team if stomach upset is troublesome.
- Tell your prescriber about any heart-rhythm problems or other medicines that affect the heart rhythm.
- Keep your monitoring and pregnancy-care appointments, as treatment may be reviewed and adjusted.
- Tell your team about all other medicines you take, including pharmacy and herbal products.
Weighing it up
Advantages & disadvantages of Spiramycin
Advantages
- Can help reduce the chance of toxoplasmosis passing from a pregnant woman to her baby.
- Taken by mouth and concentrates in the placenta, where it is needed.
- A long-established macrolide antibiotic with experience of use in pregnancy.
Disadvantages
- Commonly causes stomach upset, such as nausea and diarrhoea.
- Can affect the heart's rhythm (the QT interval) in some people.
- A specialist medicine that needs prescribing and supervision rather than routine use.
Practical use
Good to know
It helps to know that spiramycin is used in pregnancy because it gathers in the placenta and can help reduce the chance of toxoplasmosis reaching the baby, but it is a specialist decision and is part of wider care that may include extra tests. The most common side effects are stomach-related, such as nausea, diarrhoea or tummy discomfort. Like some other macrolides, it can occasionally affect the heart's electrical rhythm (the QT interval), so tell your team about any heart-rhythm problems or other medicines that do the same. It is important to take the full course as advised and to keep any monitoring appointments, since the situation in pregnancy may be reviewed and treatment adjusted. Always tell the team about all the other medicines you take.
Who should not take it / use with caution
- People who have had a serious allergic reaction to spiramycin or other macrolides should not take it.
- It is used with caution in people with certain heart-rhythm problems, including a long QT interval.
- It should only be used under specialist supervision, particularly in pregnancy.
Monitoring
- Reviewing how the pregnancy and infection are progressing, with any extra tests advised.
- Watching for stomach upset and, where relevant, heart-rhythm effects.
- Adjusting treatment over time based on specialist assessment.
Side effects
- Nausea, diarrhoea or stomach discomfort, which are the most common effects.
- Less commonly, changes in the heart's rhythm (the QT interval).
- Rarely, allergic reactions or skin reactions, which should be reported.
Key interactions
- It can interact with other medicines that affect the heart's QT interval, so these are reviewed together.
- Tell your team about all your medicines, as macrolides can interact with several of them.
- Always mention pharmacy and herbal products as well as prescribed medicines.
Available as: Tablets taken by mouth.
Answers
Spiramycin: frequently asked questions
What is spiramycin used for?
Its main use is in pregnancy, to help reduce the chance of toxoplasmosis, an infection caused by a parasite, being passed from the mother to the unborn baby.
Why is it used in pregnancy?
Spiramycin concentrates in the placenta, where it can help limit the spread of the toxoplasmosis parasite from mother to baby, especially when caught early.
What are the most common side effects?
Stomach-related effects such as nausea, diarrhoea or tummy discomfort are the most common; tell your team if they are troublesome.
Can it affect my heart?
Like some other macrolides it can occasionally affect the heart's rhythm (the QT interval), so tell your team about any heart-rhythm problems or relevant medicines.
Should I finish the course?
Yes, take the full course as advised and keep your monitoring appointments, as treatment in pregnancy may be reviewed and adjusted.
The wider class
About Macrolide antibiotic
Spiramycin belongs to the macrolide 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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