Failure to demonstrate an advantage in combining sulphamethoxazole with trimethoprim in an experimental model of urinary infection.
Co-trimoxazole was found to have a predominantly bacteriostatic effect upon 28 urinary isolates of Enterobacteriaceae in nutrient broth and was never bactericidal in artificially infected urine. The components of co-trimoxazole were tested individually and trimethoprim was found to be at least as effective as co-trimoxazole in nutrient broth and in urine. Trimethoprim alone produced some bactericidal effect in urine but this was antagonized by sulphamethoxazole. Laboratory tests for evaluating these drugs may give a misleading impression of their activity in vivo. Further clinical comparisons should therefore be made between trimethoprim and cotrimoxazole to determine when trimethoprim should be used in preference to the combination.
D003470:Culture Media; D004338:Drug Combinations; D004755:Enterobacteriaceae / Q000187:drug effects; D006801:Humans; D008962:Models, Theoretical; D013420:Sulfamethoxazole / Q000494:pharmacology / Q000627:therapeutic use*; D014295:Trimethoprim / Q000037:antagonists & inhibitors / Q000494:pharmacology / Q000627:therapeutic use*; D014552:Urinary Tract Infections / Q000188:drug therapy* / Q000382:microbiology; D014556:Urine / Q000382:microbiology
D003470:Culture Media; D004338:Drug Combinations; D014295:Trimethoprim; D013420:Sulfamethoxazole