Examine the conc-time profiles after administration of the same dose of drugs that have different hybrid elimination rate constants (all other parameters are similar).
Please note that the change in the hybrid elimination rate constant (the dependent parameter) when the volume of distribution is constant will have to result from a proportional change in the drug total body clearance (the independent parameter).
Vcis the volume of the central compartment (volume).
αis the hybrid first-order rate constant for the distribution process (time-1).
Vdis the volume of distribution (volume).
Total body clearance (CLT)
The total body clearance is the volume of the plasma or blood that is completely cleared from the drug per unit time. It has units of volume/time. The total body clearance for a drug is constant within a patient (dose and concentration independent when the elimination processes follow first-order kinetics.
The total body clearance is a measure of the efficiency of all eliminating organs in eliminating the drug and it is the sum of all organ clearances (i.e. total body clearance is the sum of the renal clearance, hepatic clearance and all other clearances).
The total body clearance and the volume of distribution (the independent parameters determine the elimination rate constant and the half life (the dependent parameters).
