Trimethoprim in the Treatment and Long-Term Control of Urinary Tract Infection

Abstract

78% of the bacterial strains found in urinary tract infections were sensitive to 10 μg/ml of trimethoprim. Therefore, the feasibility was studied of treating urinary tract infections with trimethoprim not combined with a sulphonamide. 100 mg of trimethoprim given twice a day was too small a dose for acute urinary tract infection. A dose of 250 mg twice a day yielded a positive therapeutic result in 88% of 51 patients. Side effects were minimal. A comparison was made between 100 mg of trimethoprim and 100 mg of nitrofurantoin in long-term treatment after acute infection. Both drugs were administered in a single dose at bedtime. In the nitrofurantoin group of 55 patients 6.6% and in the trimethoprim group of 54 patients 5.9% had a recurrent infection per month of treatment. Decreased level of serum folic acid without anemia was found in some patients. The results suggest that trimethoprim alone is efficacious in the treatment of urinary infections and very suitable for long-term control of the disease.