Trimethoprim

About

About trimethoprim Key facts Who can and cannot take trimethoprim How and when to take trimethoprim Side effects How to cope with side effects of trimethoprim Pregnancy and breastfeeding Cautions with other medicines Common questions about trimethoprim Trimethoprim is an antibiotic. It's used to treat and prevent urinary tract infections (UTIs), such as cystitis. Occasionally, trimethoprim is used to treat other types of infections, such as chest infections and acne. Trimethoprim is available on prescription. It comes as tablets and as a liquid that you swallow. You'll usually take trimethoprim twice a day to treat infections. For most infections, you'll feel better within a few days. But it's important to finish your course of trimethoprim to help stop your infection from coming back. Side effects may include itching or a skin rash, but these are usually mild and short-lived. You can drink alcohol while taking trimethoprim. Tell your doctor if you do not start feeling better after taking trimethoprim for 3 days, or if you start to feel worse at any time. Most adults and children can take trimethoprim. Trimethoprim is not suitable for some people. To make sure this medicine is safe for you, tell your doctor if you: have ever had an allergic reaction to trimethoprim or any other medicine have liver or kidney problems have anaemia or low amounts of folic acid (folate) in your blood have porphyria (a rare inherited blood disorder) or any other blood disorder are trying to get pregnant or are already pregnant Always follow your doctor or pharmacist's advice, and the instructions that come with your medicine. Trimethoprim tablets contain 100mg or 200mg. The liquid contains 50mg in 5ml. The usual dose of trimethoprim to: treat urinary tract infections (UTIs) is 200mg twice a day – your doctor might recommend you double the first dose to 400mg prevent infections is 100mg once a day treat cystitis that comes on after having sex is a single dose of 100mg taken within 2 hours