|Introduction to Veterinary Pharmacokinetics:||Home||Administration||Distribution||Elimination||Modeling||Models||Glossary|
Rates, clearance controlled by...
|Stylized representation of hepatic metablism, note that the ratio of drug entering the liver to that leaving the liver remains constant, despite the change in concentration. NOTE: This principle applies to all routes of elimination.
Overall renal elimination can be a combination of three processes:
(Glomerular filtration + tubular secretion) - passive reabsorption = renal elimination
Glomerular filtration (all unbound drug - in plasma water - ends up in in GF)
Tubular secretion (only a few drugs, even protein bound)
Passive reabsorption (only a few drugs, small lipid soluble)
drug movement from renal tubule back to blood stream
Passive reabsorption can be reduced by disease (accidental) or by therapy (intentional)
|Efferent blood supply of the nephron enters/leaves the glomerular tuft, then bathes the tubule/collecting duct before leaving the kidney. A PORTION of the plasma water is diverted into the nephron as it passes.|
Nephron image courtesy of Blausen Medical