Pharmacodynamics of a concentration-dependent antimicrobial. Shown is a comparison of the simulated drug concentration profile of a concentration-dependent antimicrobial with an elimination half-life of 2 hours administered once daily or in two divided doses. Under the same total daily dose, once daily administration ensures higher Cmax/MIC ratio in presence of equal AUC/MIC ratio. Dotted line refers to a MIC of 2 mg/l. AUC, area under the plasma concentration-time curve; Cmax, peak plasma concentration; MIC, minimum inhibitory concentration.