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Active substance(s): TRIMETHOPRIM

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Read all of this leaflet carefully before you start taking this medicine.
 Keep this leaflet. You may need to read it again.
 If you have any further questions, ask your doctor or pharmacist.
 This medicine has been prescribed for you. Do not pass it on to others. It may harm them, even if their
symptoms are the same as yours.
 If any of the side effects get serious, or if you notice any side effects not listed in this leaflet, please tell
your doctor or pharmacist.
1. What Trimethoprim is and what it is used for
2. Before you take Trimethoprim
3. How to take Trimethoprim
4. Possible side effects
5. How to store Trimethoprim
6. Further information

Trimethoprim belongs to a group of medicines called antibacterials. Antibacterials are similar to
Trimethoprim is used for the prevention and treatment of infections, particularly in the urinary and
respiratory tracts.

Do not take Trimethoprim if you:
 are allergic (hypersensitive) to trimethoprim or any of the other ingredients of this medicine
 are pregnant
 have any blood disorders
 suffer from severe kidney problems, unless your doctor is checking the levels of trimethoprim in your
 suffer from severe liver problems.
Take special care with Trimethoprim
Tell your doctor before you start to take this medicine if you:
 are planning to become pregnant or breast-feeding
 have kidney problems
 have folate-deficiency anaemia (a decrease in red blood cells due to a poor diet, which can cause
tiredness, headache, a sore mouth and tongue and pale skin).
You may need to have blood tests if you take Trimethoprim for a long time, if you are a child, if you are
elderly, or if your doctor thinks you are at special risk.

Taking other medicines
Talk to your doctor if you are taking any of the following:
 azathioprine (used following organ transplant and for arthritis)
 ciclosporin (used to prevent organ rejection after transplant surgery)
 digoxin or procainamide (used to treat heart problems)
 mercaptopurine or methotrexate (used as bone marrow depressants)
 pyrimethamine (used to treat malaria)
 phenytoin (used to treat epilepsy)
 rifampicin (used to treat infections)
 warfarin (used to prevent blood clots).
Please tell your doctor or pharmacist if you are taking or have recently taken any other medicines, including
medicines obtained without a prescription.
Pregnancy and breast-feeding
Do not take Trimethoprim if you are pregnant. If you are planning to become pregnant or breast-feeding, ask
your doctor for advice before taking this medicine.
Driving and using machines
Trimethoprim is not known to affect your ability to drive or operate machinery.
Important information about some of the ingredients of Trimethoprim
Patients who are intolerant to sorbitol should note that Trimethoprim suspension contains a small amount of
sorbitol. If you have been told by your doctor that you have an intolerance to some sugars, contact your
doctor before taking this medicinal product.
Trimethoprim also contains methylparaben (E218) and propylparaben (E216), which may cause allergic
reactions (possibly delayed), and exceptionally, difficulty breathing.
Always take Trimethoprim exactly as your doctor has told you. You should check with your doctor or
pharmacist if you are not sure. You should continue to take this medicine for as long as your doctor tells you
to. Take the full course. Even if you start to feel better the original infection may still be present and may
come back if treatment is stopped.
The usual dose is:
Treatment of infections
 Adults and children over 12 years of age: 20 ml (four 5 ml spoonfuls) twice a day.
 Children aged 6 to 12: 10 ml (two 5 ml spoonfuls) twice a day.
 Children from 6 months to 5 years: one 5 ml spoonful twice a day.
 Children from 6 weeks to 5 months: 2.5 ml (half a 5 ml spoonful) twice a day.
The treatment should continue for at least one week but no longer than two weeks.
For long term treatment and for the prevention of infections
 Adults and children over 12 years of age: 10 ml (two 5 ml spoonfuls) at night.
 Children aged 6 to 12 years: one 5 ml spoonful at night.
 Children aged 6 months to 5 years: 2.5 ml (half a 5 ml spoonful) at night.
Elderly: The adult dose may need to be reduced depending on how well your kidneys function. Your doctor
will calculate your dose for you.
Patients with reduced kidney function:
It may be necessary to reduce the dosage if you are suffering from kidney problems. Your doctor will
calculate your dose for you.

Dialysis patients:
Trimethoprim is removed by dialysis. Blood tests will be carried out before and after dialysis.
If you take more Trimethoprim than you should
If you (or someone else) swallow a lot of this medicine all together, or if you think a child has swallowed
any of the medicine, contact your nearest hospital casualty department or your doctor immediately. An
overdose is likely to cause a lowering of the development of blood cells in the body, which is identified by
the following symptoms: fatigue or tiredness, trouble breathing, quick heart rate, difficulty staying warm,
pale skin, dizziness or light-headedness, fever, excessive bruising or bleeding and nosebleeds. Please take
this leaflet, any remaining medicine and the container with you to the hospital or doctor so that they know
which medicine has been consumed.
If you forget to take Trimethoprim
If you forget to take a dose, take one as soon as you remember, unless it is nearly time to take the next one.
Do not take a double dose to make up for a forgotton dose. Take the remaining doses at the correct time.
If you have any further questions on the use of this product, ask your doctor or pharmacist.
Like all medicines, Trimethoprim can cause side effects, although not everybody gets them.
If the following happens, stop taking Trimethoprim and tell your doctor immediately or go to the casualty
department at your nearest hospital:
 an allergic reaction (swelling of the lips, face or neck leading to severe difficulty in breathing; skin
rash or hives)
 Aseptic meningitis can occur in some patients. This may show as a combination of symptoms such
as headache, fever, stiff neck, tiredness, feeling ill and your eyes become very sensitive to bright
 Severe skin reactions such as exfoliative dermatitis (itchy, scaly, flaking, swollen skin), erythema
multiforme (circular, irregular red patches), Stevens-Johnson syndrome (severe skin rash with
flushing, fever, blisters or ulcers) or toxic epidermal necrolysis (severe rash involving reddening,
peeling and swelling of the skin that resembles severe burns).
These are very serious but rare side effects. You may need urgent medical attention or hospitalisation.
The following side effects have been reported rarely:
 feeling sick or being sick
 headache
 upset stomach
Other side effects may include:
 Abdominal pain
 Fever, muscle pain
 Sore mouth, swollen tongue
 Skin redness, skin rashes and itching
 Sensitivity to light
 Anaemia (characterised by unusual tiredness or weakness)
 Jaundice (yellowing of the skin or whites of the eyes), changes in liver enzymes (seen in tests)
 Altered number and type of blood cells. If you get increased bruising, nose bleeds, sore throats or
infections you should consult your doctor. Too much potassium in the blood (you may experience
muscle cramps or pain, irregular heartbeats, unusual tiredness or weakness)
 Kidney problems: increase in blood creatinine and urea levels (seen in tests).

Reporting of side effects
If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects
not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme at: By reporting side effects you can help provide more information on the
safety of this medicine.

Keep this medicine out of the sight and reach of children. Do not take Trimethoprim after the expiry date
that is stated on the outer packaging. The expiry date refers to the last day of that month.
Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to
dispose of medicines no longer required. These measures will help to protect the environment.
What Trimethoprim contains:
 The active ingredient is trimethoprim.
 The other ingredients are sorbitol, agar, methylparaben (E218), propylparaben (E216), polysorbate and
saccharin sodium.
What Trimethoprim looks like and contents of the pack:
 Trimethoprim 50 mg/5 ml Suspension is a white, opalescent, viscous suspension supplied in glass bottles.
 Trimethoprim is available in bottles of 100 ml.
Marketing Authorisation Holder and Manufacturer
Marketing Authorisation holder and company responsible for manufacture: TEVA UK Limited, Eastbourne,
BN22 9AG.
This leaflet was last revised: March 2016
PL 00289/0203

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Source: Medicines and Healthcare Products Regulatory Agency

Disclaimer: Every effort has been made to ensure that the information provided here is accurate, up-to-date and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. This information has been compiled for use by healthcare practitioners and consumers in the United States. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective or appropriate for any given patient. If you have questions about the substances you are taking, check with your doctor, nurse or pharmacist.