(2001; 179 pages)
Tablet, 100mg, 200mg
Trimethoprim is an inhibitor of folic acid metabolism that is active against many Gram-positive cocci and Gram-negative bacilli.
Trimethoprim is well absorbed from the gastrointestinal tract and widely distributed in the tissues. It has a plasma halflife of about 11 hours and is excreted in the urine. It crosses the placenta and is excreted in breast milk.
Treatment of urinary tract infections and prostatitis in adults.
Dosage and administration
Urinary tract infections in adults
Women: 300 mg orally every 24 hours for 3 days (for uncomplicated infections).
Men: 300mg orally every 24 hours for at least 14 days.
Prostatitis in adults
200mg orally every 12 hours for 4 - 6 weeks.
• Pregnancy during the first trimester.
• Renal impairment (creatinine clearance <15ml/minute).
Trimethoprim should be used with caution in patients with folate deficiency, since haematological changes can occur. Folinic acid should be administered to these patients.
Use in pregnancy
Safe use in pregnancy has not been established. Treatment should be deferred until after the first trimester of pregnancy.
The most frequent adverse effects are skin rashes and urticaria.
Rarely, exfoliative dermatitis and toxic epidermal necrolysis have been observed. Gastrointestinal disturbances have also been reported. Haematological reactions may occur in patients with folate deficiency.
Trimethoprim inhibits hepatic metabolism.
Treatment is supportive and symptomatic.
Tablets should be stored in tightly closed containers, protected from light.