Drug X is given intravenously, using two different regimens, to the same patient on two different occasions. On both occasions, there is no measurable amount of the drug in plasma prior to its administration. On both occasions, the volume of distribution of X is 0.85 L/kg and the plasma half-life is six hours.
Regimen A: continuous intravenous infusion of 10 mg/kg/h, with no loading dose.
Regimen B: a loading dose of 50 mg/kg given rapidly intravenously, then a continuous intravenous infusion of 10 mg/kg/h.
Using Regimen A, the plasma concentration of X after 48 hours was 100 mg/L.
Using Regimen B, the plasma concentration of X after 48 hours would most closely approximate:
Select one of the following: