[Pharmacokinetic studies with the combination sulfamoxole/trimethoprim in animals and men (author's transl)].

The pharmacokinetics of the 5:1 combination of N1-(4,5-dimethyl-2-oxazolyl)-sulfanilamide (sulfamoxole) and 2,4-diamino-5-(3,4,5-trimethoxy-benzyl)-pyrimidine (thrimethoprim) (CN 3123, Nevin, Supristol) corresponds to the well known data of the single substances. Investigations on blood level, concentration in plasma water and excretion via urine and bile were done on experimental animals and with therapeutic dosage (single and repeated administration) on men. There were no alterations of the kinetics of the single substances due to drug interaction during simultaneous administration, neither qualitatively nor quantitatively. The dosage schedule elaborated is as follows: dosage interval=12 h, ratio initial dose: maintenance dose=2:1. For adults this regimen with a maintenance dose of 400 mg sulfamoxole and 80 mg trimethoprim results in a steady state of the minimal concentrations immediately before the following dose. These minimal concentrations in plasma water exceed the minimal inhibitory concentrations determined in vitro for most pathogens by several times.