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Active substance(s): TRIMETHOPRIM

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TRIMETHOPRIM 50mg / 5ml Suspension
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 gets serious, or if you notice any side effects not listed in this leaflet, please tell your doctor.
In this leaflet:
What Trimethoprim is and what it is used for
Before you take Trimethoprim
How to take Trimethoprim
Possible side effects
How to store Trimethoprim
Further information
Trimethoprim is an antibiotic which is used to treat or prevent bacterial infections, including urinary tract infections, in adults
and children.

Do not take Trimethoprim if you:

are allergic to trimethoprim or any of the ingredients of Trimethoprim (see Section 6 and end of Section 2).

have severe liver or kidney failure.

have megaloblastic anaemia (deficient in vitamin B12 or folate) or other blood disorders.

are pregnant

have hereditary fructose intolerance or an intolerance to some sugars.
Trimethoprim must not be given to children under 4 months old.
Before taking Trimethoprim, consult your doctor if you:

have other kidney problems.

have folate deficiency; you may need to take a folate supplement and have regular blood tests.

are elderly or if you suffer from porphyria (a rare blood disorder which can affect your skin or nervous system).
Patients on long term treatment with Trimethoprim may need regular blood tests. Carers and patients should look out for the
following signs of blood disorders:- symptoms include fever, sore throat, rash, mouth ulcers, purpura (purple spots or patches
on the skin), bruising or bleeding. If any of these occur seek immediate medical attention.
Taking other medicines
Please tell your doctor if you are taking or have recently taken any other medicines, including those obtained without a
prescription. Trimethoprim may interfere with other medicines you may be taking. Especially, tell your doctor if you are taking
any of the following:

Ramipril (used to treat high blood pressure)

Phenytoin (for epilepsy)

Digoxin or Procainamide (heart medications)

Rifampicin (an antibiotic)

Ciclosporin or azathioprine (used to prevent rejection in transplantation)

Bone marrow suppressants (used to treat some forms of cancer)

Amiodarone (used to help your heart beat more regularly)

Warfarin (used to thin the blood)

Repaglinide (used to treat diabetes)

Pyrimethamine (used to treat malaria)

Lamivudine (used to treat HIV)

Oestrogen (contraceptive pill)

Methotrexate (used to treat cancer or for your immune system)

Amantadine (used to treat Parkinsons disease, multiple sclerosis, flu or shingles)

Eplerenone (used to treat high blood pressure)

Dapsone (used to treat bacterial infections)

Diuretics (water tablets) which help increase the amount of urine you produce
Taking Trimethoprim with food and drink:
Trimethoprim can be taken with or without food.
Pregnancy and breast-feeding
Do not take Trimethoprim if you are pregnant.
As with all medicines, ask your doctor for advice before taking Trimethoprim if you are breast-feeding.
Important information about some of the ingredients of Trimethoprim
Trimethoprim contains

Sorbitol (E420): see your doctor before taking this medicine if you have an intolerance to some sugars

methylhydroxybenzoate (E218) and propylhydroxybenzoate (E216): may cause allergic reactions (possibly delayed).
Always take Trimethoprim exactly as your doctor has told you. You should check with your doctor or pharmacist if you are not
sure. Shake well before use. The usual dose is:
Adults (including the elderly) and children over 12 years of age:
Urinary tract infections and
Four 5ml spoonfuls twice daily
other susceptible infections
Long-term prevention of
Two 5ml spoonfuls at night
recurring urinary tract infections
Children 4 months to 12 years of age:
Urinary tract infections and
4 months - 2 years
other susceptible infections
2 years - 6 years
6 years - 12 years
Long-term prevention of
4 months - 2 years
recurring urinary tract infections
2 years - 8 years
8 years - 12 years

2.5ml (half a spoonful) twice daily
One 5ml spoonful twice daily
Two 5ml spoonfuls twice daily
2.5ml (half a spoonful) at night
One 5ml spoonful at night
Two 5ml spoonfuls at night

Renal Impairment
It may be necessary to reduce the dosage if you are suffering from kidney problems. Your doctor will advise you.
If you forget to take Trimethoprim
Take the dose as soon as you remember, unless its nearly time for your next dose. Do not take a double dose to make up for
the missed dose.
If you take more Trimethoprim than you should
If you take too much Trimethoprim, go immediately to your nearest hospital casualty department, taking your medicine bottle
with you to show what you have taken.

If you stop taking Trimethoprim
Remember to keep taking this medicine until your doctor tells you to stop. Do not stop just because you feel better. If you stop
too early, your infection may return, or get worse.
If you have any further questions on the use of Trimethoprim, ask your doctor or pharmacist.

Like all medicines, Trimethoprim can cause side effects, although not everybody gets them.
STOP taking Trimethoprim and contact your doctor immediately if you experience a rare allergic reaction, as you may
need emergency treatment. Symptoms include:

swelling of the face and/or throat

difficulty breathing

a rash

itching or skin reactions with blistering or peeling skin
Very rare (fewer than 1 in 10,000 people are affected) allergic reactions are:


chest pain

red patches on skin

megaloblastic anaemia (an imbalance in certain types of blood cell), particularly during prolonged treatment at high
doses, symptoms are change in skin colour, pale skin colour, loss of appetite, tingling and numbness of hands and feet
Patients are advised to have their blood checked regularly

aseptic meningitis (swelling of the layers lining the brain, without bacterial infection). Symptoms are headache,
stiff neck, nausea and vomiting, abnormal sensitivity to light, muscle pain, confusion

uveitis - inflammation of lining of the eye

fever (high temperature) or frequent infections

sudden wheeziness or difficulty breathing

mouth ulcers, cold sores and ulcers or soreness of your tongue

skin lumps or hives (raised, red or white itchy patches of the skin)

blisters on your skin or inside of your mouth, nose, vagina or bottom

the appearance of a rash or sunburn when you have been outside (even on a cloudy day)

low levels of salt in your blood. Symptoms include irregular heart beat, dry mouth or not having any energy

feeling weak, tired or listless, pale skin (anaemia)

heart problems

jaundice (the skin and whites of the eyes turn yellow)

muscle pain (myalgia).
Rare (more than 1 in 10,000 to less than 1 in 1,000 people) side effects can include:

erythema multiforme (raised red areas on the skin and mucous membranes [moist linings of the internal parts of
our body])

skin sloughing (saggy skin).
Very common (more than 1 in 10 people)

high levels of potassium in your blood which can cause abnormal heart beats (palpitations).

Common allergic reactions (less than 1 in 10 people)

an infection called thrush or candidiasis which can affect your mouth or vagina. It is caused by a fungus


feeling sick (nausea)


skin rashes.
Uncommon (less than 1 in 100 people)

being sick (vomiting).

If any of the side effects gets serious, or if you notice any side effects not listed in this leaflet, please tell your doctor.
Keep out of the reach and sight of children. Store in the original container.
Do not use your medicine after the expiry date which is stated on the label or carton.
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.
Trimethoprim contains:

the active substance: trimethoprim - each 5ml of the oral suspension contains trimethoprim 50mg.

the other ingredients: agar, polysorbate 80, saccharin sodium, sorbitol (E420), methylhydroxybenzoate (E218),
propylhydroxybenzoate (E216) and purified water (see end of Section 2: ‘Important information’).
What Trimethoprim looks like and contents of the pack
Trimethoprim is a white, opalescent, viscous oral suspension. This medicine contains no flavour. It is available in 100 ml
amber glass bottles with pilfer-proof screw cap and expanded polyethylene liner.
Marketing Authorisation Holder and Manufacturer
Pinewood Laboratories Ltd., Ballymacarbry, Clonmel, Co. Tipperary, Ireland

This leaflet was last updated in 03/2010


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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.