Trimethoprim is a widely used antibiotic designed to treat bacterial infections, most notably urinary tract infections (UTIs). It works by inhibiting bacterial DNA synthesis, halting the growth of the bacteria responsible for the infection.
It is typically prescribed for short-term use in acute UTIs, particularly in women, but may also be used as a long-term prophylactic treatment for recurrent infections. Trimethoprim is also effective in certain respiratory or gastrointestinal infections when clinically indicated.
Standard formulations include 100mg (for prophylaxis) and 200mg (for active infection). For uncomplicated UTIs, it is commonly prescribed as 200mg twice daily for 3 days. In cases requiring extended coverage or prophylactic use, dosage and duration will be tailored by a GP.
Trimethoprim is well-absorbed and typically begins to relieve symptoms within the first 1–2 days of treatment. It is important to complete the entire prescribed course, even if symptoms resolve early, to prevent resistance and recurrence.
How It Works
Trimethoprim blocks the bacterial enzyme dihydrofolate reductase, essential for DNA replication. This action prevents bacteria from multiplying, allowing the immune system to eliminate the remaining infection.
Why Choose Trimethoprim
Rapid and reliable UTI symptom relief
Targeted action against most common urinary pathogens
Available in short-course or long-term prophylactic dosing
Trusted by GPs and widely used in UK healthcare settings
Important Note
Take Trimethoprim exactly as prescribed. It should be taken with water and can be taken with or without food. Ensure adequate fluid intake during treatment. Do not share with others, even if symptoms appear similar.
Report any rashes, fever, or unusual symptoms to a healthcare provider, particularly if you have a history of sulfa allergies or kidney/liver problems.
