Pharmacokinetics

Question 1

factors that influence drug absorption

Answer 1

pH, surface area available for absorption, blood flow to the absorption site, contact time at the absorption surface, p-glycoprotein

Question 2

in the blood stream, what do acidic and basic drugs bind to

Answer 2

acidic bind to plasma albumin

basic bind to alpha 1 acid glycoprotein

Question 3

what drug given with warfarin can displace warfarin bound to albumin hence leading to an increase in free warfarin

Answer 3

sulfonamides

Question 4

where are the enzyme systems located for phase I and II reactions

Answer 4

phase I: ER
phase II: cytosol
of the liver

Question 5

which cytochrome P450 family metabolizes more than 50% of therapeutic drugs

Answer 5

CYP3A4

Question 6

what pharmacological agents induces CYP3A4

Answer 6

carbamazepine (also metabolized by it too)

Question 7

what pharmacological agents inhibits CYP3A4 hence leaving active drug in system even longer

Answer 7

CCRAAMF

Cimetidine
Chloramphenicol
Ritonavir - HIV protease Inhibitor
Amiodarone
Azole Antifungals
Macrolide antibiotics
Furanocoumarins (seen in grape fruit)

Question 8

cytochrome that metabolizes acetaminophen

Answer 8

CYP2E1

Question 9

explain what happens when someone overdoses on acetaminophen

Answer 9

the glutathione storage is used up causing a build up of NAPQI leading to cell death

Question 10

what can be given when a person overdoses on acetaminophen

Answer 10

N acetyl cysteine to replenish the storage of glutathione