mean residence time (in pharmaco- and toxicokinetics) (MRT)

Average time a substance remains in an animal body or an organ after rapid intravenous injection.
Note 1:    Like clearance, its value is independent of dose in most cases.
Note 2:    After an intravenous bolus
t_r= A_m/A
where t_r is the MRT, A is the area under the plasma concentration-time curve, and A_m is
the area under the moment curve.
Note 3:    For a drug with one-compartment distribution characteristics, MRT equals the recipro-
cal of the elimination rate constant.