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Trimethoprim Tablets 100mg, 200mg

Last Updated on eMC 15-Feb-2017 View changes  | Actavis UK Ltd Contact details

The Patient Information Leaflet (PIL) is the leaflet included in the pack with a medicine. It is written for patients and gives information about taking or using a medicine. It is possible that the leaflet in your medicine pack may differ from this version because it may have been updated since your medicine was packaged.

Please click on the link to the left to view the PIL in PDF format.

Text only version for the visually impaired
Below is a text only representation of the Patient Information leaflet. The original may contain images or tables and can be viewed in PDF format using the link to the left. This PIL may be available from the RNIB in large print, Braille or audio CD. For further information please call the RNIB Medicine Leaflet line on 0800 198 5000. The product code(s) for this leaflet is/are: PL 00142/0224, PL 00142/0225.

Trimethoprim Tablets 100mg, 200mg


Trimethoprim 100mg and 200mg tablets

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.


1 What Trimethoprim tablets are and what they are used for
2 Before you take
3 How to take
4 Possible side effects
5 How to store
6 Further information

1 What Trimethoprim tablets are and what they are used for

Trimethoprim is a type of antibacterial medicine which works by killing bacteria. Trimethoprim tablets may be used:

  • to treat a wide range of infections including urinary infections and respiratory tract infections.
  • for long-term prevention of recurrent urinary tract infections.

2 Before you take

Do not take Trimethoprim tablets and tell your doctor if you:

  • are allergic (hypersensitive) to trimethoprim or any of the other ingredients in the tablet (see section 6)
  • are pregnant
  • have any blood disorder
  • have severe kidney disease
  • have severe liver disease
  • Trimethoprim should not be given to premature babies or babies during the first few weeks of life.

Check with your doctor or pharmacist before taking Trimethoprim tablets if you have:

  • kidney disease or are having dialysis treatment
  • a deficiency of folic acid (may cause anaemia).

Taking other medicines

Please tell your doctor or pharmacist if you are taking or have recently taken any other medicines, including medicines obtained without a prescription. Especially:

  • antibiotics such as rifampicin
  • anticoagulants to prevent your blood clotting such as warfarin
  • ciclosporin (to prevent rejection after transplantation)
  • digoxin (to treat heart conditions)
  • phenytoin (to treat epilepsy)
  • pyrimethamine (to treat malaria)
  • bone marrow depressants
  • spironolactone (to treat fluid build up).

Pregnancy and breast-feeding

Trimethoprim should not be used in pregnancy.

If you are breast-feeding, ask your doctor or pharmacist for advice before taking this medicine.

Sugar intolerance

If you have been told you have an intolerance to some sugars, contact your doctor before taking this medicine, as it contains a type of sugar called lactose.

Blood tests

If you are having treatment over a long time, your doctor may carry out regular blood tests.

3 How to take

Always take Trimethoprim tablets exactly as your doctor has told you. If you are not sure, check with your doctor or pharmacist.

Swallow the tablets with a glass of water at the same times each day.


  • Severe or sudden infections: (e.g. uncomplicated bacterial cystitis in women) treatment will usually be between 3-14 days, according to the type and severity of infection.
    Your doctor may double your first dose.
    • Adults and children over 12 years: 200mg twice a day.
    • Children 6-12 years: 100mg twice a day.
    • Children under 6 years: Not recommended; a more suitable dosage form should be used in this age group.
  • Long-term treatment and prevention therapy:
    • Adults and children over 12 years: 100mg at night.
    • Children 6-12 years: 50mg at night. The usual dose is around 2mg per kg body weight of the child per day.

Elderly: doses may be reduced in elderly patients, according to kidney function.

If you take more than you should

If you (or someone else) swallow a lot of tablets at the same time, or you think a child may have swallowed any contact your nearest hospital casualty department or tell your doctor immediately.

If you forget to take the tablets

If you forget to take a dose take it as soon as you remember it and then take the next dose at the right time. Do not take a double dose to make up for a forgotten dose.

If you stop taking the tablets

Do not stop taking Trimethoprim tablets because you feel better. Take the tablets for as long as your doctor has told you or your problem may come back.

4 Possible side effects

Like all medicines, Trimethoprim tablets can cause side effects, although not everybody gets them. Please tell your doctor or pharmacist if you notice any of the following effects or any effects not listed.

Contact your doctor at once if you get an allergic reaction such as swelling of the face, lips, tongue or throat, difficulty breathing, shock or collapse.

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 light.

Tell your doctor if you notice any of the following side effects or notice any other effects not listed:

Blood: altered number and type of certain 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).

Stomach: feeling or being sick, sore mouth, discomfort, this is usually mild and disappears after stopping the tablets.

Skin: sensitivity to light, skin rashes which may be itchy, 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).

Liver: changes in liver enzymes (seen in tests), jaundice (yellowing of skin or whites of the eyes)

Kidney: increase in blood creatinine and urea levels (seen in tests)

Muscles: muscle pain.

Other: red, swollen tongue, headache.

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.

5 How to store

Keep out of the reach and sight of children.

Store below 25°C in a dry place.

Do not use Trimethoprim tablets after the expiry date stated on the label/carton/bottle. 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.

6 Further information

What Trimethoprim tablets contain

  • The active substance (the ingredient that makes the tablets work) is trimethoprim. Each tablet contains either 100mg or 200mg of the active substance.
  • The other ingredients are colloidal silicon dioxide, lactose, macrogol, magnesium stearate, povidone, sodium starch glycollate, stearic acid, microcrystalline cellulose (E460).

What Trimethoprim tablets look like and contents of the pack

Trimethoprim tablets are white, circular, uncoated tablets.

Pack sizes are 6, 14 and 28 tablets

Marketing Authorisation Holder and Manufacturer

EX32 8NS

This leaflet was last revised in January 2017

EX32 8NS

50917360 BBBA0412

Company contact details

Company image

Actavis UK Ltd, a subsidiary of Accord Healthcare Ltd, Whiddon Valley, Barnstaple, Devon, EX32 8NS, UK


+44 (0)1271 346 106

Medical Information e-mail

+44 (0)1271 385 200

Medical Information Direct Line

+44 (0)1271 385 257

Before you contact this company: often several companies will market medicines with the same active ingredient. Please check that this is the correct company before contacting them. Why?

Active ingredients


Legal categories

POM - Prescription Only Medicine

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