[Pharmacotherapy and kidney dysfunction]

Essential for drug dose adjustment is the glomerular filtration rate (GFR) not the serum creatinine level. In acute disease, a loading dose must be given that usually corresponds to the normal dose. The eliminated half-life is used to estimate the administration interval. For anti-infective drugs with a concentration-dependent effect, the target is the high peak such as for daptomycin, linezolide, and colistin. For anti-infective drugs with a time-dependent effect, the target is the high trough such as for piperacillin, meropenem and vancomycin. Such drugs with a time-dependent action should best be administered by infusion not by bolus dosing. With continuous renal replacement therapy (CRRT), the total filtration rate corresponds to a GFR of 30-50 ml/min and many antibiotics will not need a dose reduction on CRRT. After intermittent hemodialysis, a new loading dose should be given to ascertain sufficiently high concentrations in the interval until the next dose or next dialysis.