Pharmacokinetics of ceftriaxone following intravenous administration of a 3 g dose

Summary The pharmacokinetic parameters of total (bound and unbound) and free (unbound) ceftriaxone in six healthy volunteers after intravenous injection of 39 were compared with low-dose data from a previous study. The dose-dependent behaviour of total drug was considerably more pronounced after the 3 gram dose. In contrast, total body clearance (Cl _S ^F =258 ml/min), renal clearance (Cl _R ^F =170 ml/min) and volume of distribution (V _D(β) ^F =168 l) of free (unbound) drug did not differ from the data reported earlier. There was no significant change in biological half-life (t_1/2(β)=7.8 h) or in the fraction excreted unchanged in urine (f_u=0.67).