Trimethoprim is an antibiotic. It is used on its own or together with other medicines to treat certain bacterial infections of the urinary tract, lungs, ears and stomach.
Take Trimethoprim exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.
This medicine is best taken with food to minimise any stomach discomfort that it may cause. Try to take it same time each day.
Take Trimethoprim at regular intervals as instructed. Do not skip any doses. Continue to take it even when you feel better. You must complete the entire course of antibiotic. If you don't, the infection will not clear completely.
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.
DO NOT double a dose under any circumstances.
If you often forget to take your medicine, let your doctor and pharmacist know.
Alert your doctor if you have a blood disorder known as megaloblastic anaemia caused by folic acid deficiency as Trimethoprim may not be suitable for you.
Inform your doctor if you have kidney or liver disease.
Let your doctor know if you are pregnant or breastfeeding.
For as long as you are taking this medicine, you may need to have regular blood tests to check your body’s response to Trimethoprim. Your doctor will advise you about how often you need to have blood tests.
Trimethoprim may cause any of the following side effects: headache, rash, itch, nausea, stomach discomfort and vomiting.
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Inform your doctor and pharmacist if you are taking any of these medicines:
- medicines for epilepsy (fits or seizures) e.g. phenytoin
- medicines used in organ transplant or certain immune disorders e.g. azathioprine, mercaptopurine
- pyrimethamine (medicine for malaria)
- medicines for heart disease e.g. digoxin, procainamide,
- antibiotic e.g. rifampicin, dapsone,
- water pills e.g. hydrochlorothiazide
- medicines for diabetes e.g. repaglinide
- blood-thinning medicines e.g. warfarin
This list does not include all medicines that may interact with Trimethoprim.
Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
Store in a cool, dry place away from the reach of children.
Medicines must not be used past the expiry date.