Metabolism and Excretion Flashcards
List 7 inducers
Rifampin St. John's Wort Phenobarbitol Phenytoin Carbamazepine Tobacco Smoke Ethanol
List 7 inhibitors
Cimetidine Erythromycin/ Clarithromycin Ketoconazole/ Azole antifungals Fluoxetine Grapefruit HIV protease inhibitors Omeprazole
What type of metabolism is affected by old age?
Mostly cytochrome metabolism so you have to adjust dosage
What is P-glycoprotein?
Transporter which plays a role in the elimitation of xenobiotics
What do P-glycoproteins do to xenobiotics at the GI tract?
They reduce absorption by expelling them from the cells
What do P-glycoproteins do to xenobiotics at the liver and kidey?
They enhance elimination
P-glycoproteins share the same inducers and inhibitors at what mechanism?
Cytochrome P450
What would happen to the plasma concentration of xenobiotics if you induce P-glycoproteins?
Cp would decrease
What would happen to the plasma concentration of xenobiotics if you inhibit P-glycoproteins?
Cp would increase
What kind of drugs do kidneys excrete?
water soluble
non volatile
Describe glomerular filtration
drug less than 69000 MW
Rate- 120ml/min
No protein bound drug
Describe Active tubular secretion
Directly from blood to urine
120-600ml/ml
strong acids and bases in proximal tubule
Protein binding does not effect secretion half-life
Rate of tubular reabosorption
1ml/min
where does passive diffusion of the kidney occur?
Proximal and distal tubule. Weak acids or bases depends on pH of urine
Active reabsorption is important for what molecules?
Endogenous
