With continuous arteriovenous haemodiafiltration (CAVHD), time-averaged clearance rates are higher than with intermittent haemodialysis. Indeed, drug removal rates may be high enough to warrant dose adjustment. In this study we measured the rate of drug clearance by CAVHD for 7 commonly used antibiotics: cefuroxime, cefotaxime, ceftazidime, imipenem, ciprofloxacin, tobramycin and vancomycin. By combining our data on clearance rates by CAVHD with literature data on drug distribution volumes and nonrenal clearance rates, we developed guidelines for drug dosage in intensive care patients treated by CAVHD. Dose adjustments during CAVHD treatment were deemed necessary for cefuroxime, ceftazidime, tobramycin and vancomycin.