Average plasma concentrations of ertapenem following a single 30 minute intravenous infusion of a 15 mg/ kg (up to a maximum dose of 1 g) dose in patients 3 to 23 months of age were 103.8 micrograms/ ml (Cmax) at 0.5 hour postdose (end of infusion), 13.5 micrograms/ ml at 6 hour postdose, and 2.5 micrograms/ ml at 12 hour postdose.