Systemic Clearance (CL or CLs)in pharmacokinetics represents the rate at which a drug gets removed from the bloodstream. Clearance is determined from non-compartmental analysis following IV dosing. It represents total additive clearance from all potential clearing organs (e.g., liver, kidneys, etc.). We measure clearance values in units of volume/time and think of it as a proportionality constant between drug concentration and elimination rate. The non-compartmental pharmacokinetic equation for clearance is CL = Dose/AUC.