The potential for significant drug removal during an 8-hr-or-longer sustained low-efficiency dialysis session is evident by the limited number of studies available. Because significant amounts of drug may be removed by sustained low-efficiency dialysis combined with altered pharmacokinetic variables in critically ill patients, the risk for suboptimal drug concentrations and pharmacodynamics must be considered. Appropriate dose and calculation of dosing intervals is essential to provide adequate antibiotic therapy in these patients. It is recommended that institutions who utilize sustained low-efficiency dialysis establish dosing guidelines for all pharmacists and physicians to follow to provide consistent delivery of antibiotics at adequate concentrations.