Elimination of a drug from the plasma is quantified in terms of its clearance. The term has the same meaning as the familiar renal creatinine clearance, which is a measure of removal of endogenous creatinine from the plasma. Clearance values can provide useful information about the biological fate of a drug. There are pharmacokinetic methods for calculating total body and renal clearance, and the difference between these is commonly taken to represent hepatic clearance. Renal clearance of a drug that is eliminated only by filtration by the kidney obviously cannot exceed the glomerular filtration rate (adult male 124 ml/min, female 109 ml /min). If a drug is found to have a renal clearance in excess of this, then it must in addition be actively secreted by the kidney tubules, e.g. benzylpenicillin (renal clearance 480 ml/min).

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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