Pharmacology

Question 1

Define drug efficacy

Answer 1

the measure of drug response elicited by a particular drug

Question 2

Define drug potency

Answer 2

the measure of the concentration of drug required to elicit a certain response

Question 3

What characteristics would you expect of a drug with a very low volume of distribution (Vd)?

Answer 3

large, charged, plasma protein-bound, hydrophillic

Question 4

What relative volume of distribution would you expect of a small, hydrophobic, uncharged drug?

Answer 4

large Vd

Question 5

Are acidic or basic drugs more likely to be reabsorbed in the DCT (pH 5.4)?

Answer 5

With pH below 7.4, the equilibrium tends towards HA and HB+, meaning the uncharged acidic drugs are more likely to be reabsorbed

Question 6

What are the main mechanisms of Phase I metabolic reactions?

Answer 6

Transformations into a more polar molecule; redox, hydrolysis

Question 7

What are the two most important P450 oxidases in Phase I reactions?

Answer 7

CYP3A4 “workhorse”
CYP2D6 “bottleneck”

Question 8

What are the main mechanisms of Phase II metabolic reactions?

Answer 8

conjugations (sulfation, methylation, acetylation, glucoronidation)

Question 9

What is the main result of a drug going through a Phase II metabolic reaction?

Answer 9

Water soubility is typically enhanced to the point of secretion into urine and excreted from body

Question 10

What are 3 examples of zero-order elimination drugs?

Answer 10

Aspirin, Phenytoin, Ethanol