It is important to note that higher does not always mean faster rate of drug disappearance from the body ( larger and shorter ).
Gentamicin
CLT = 0.07 L/hr/kg
Vd = 0.2 L/kg
Rifampin
CLT = 0.2 L/hr/kg
Vd = 1 L/kg
Gentamicin:
k = CLT/Vd = 0.35 hr-1
Rifampin:
k = CLT/Vd = 0.2 hr-1
The total body clearance of rifampin is higher than that of gentamicin. However, because rifampin Vd is larger, the rate of decrease of the plasma rifampin concentration is slower than that of gentamicin (smaller k, longer half life).
