[Pharmacokinetics of trimethoprim and sulfametrol in patients with end stage renal failure and hemodialysis treatment (author's transl)].

In 6 patients with regular dialysis treatment the pharmacokinetics of intravenously administered trimethoprim and sulfametrol were investigated not only during dialysis procedure but also during the dialysis-free interval. Half-life of the free plasma sulfametrol component is normal even in cases with absent renal function and can be markedly reduced by hemodialysis treatment. The N4-acetylated main metabolite of the sulfonamide is - similar to trimethoprim - hardly dialyzable. Half-life of the latter drug component is prolonged in patients with far advanced renal failure. Due to the excellent dialysanceof the free plasma sulfonamide component the elimination of total sulfametrol is normal during hemodialysis despite cumulation of the N4-acetylated metabolite. Because of the tendency of this metabolite to cumulation, in dialysis patients the compound preparation of trimethoprim and sulfametrol should be used only for trasient treatment of acute infections.