Pharmacology

Question 1

competitive inhibitors

Answer 1

• resemble substrate
• can be overcome by increasing substrate
• binds active site
• does not affect Vmax
• increases Km
• less potent

Question 2

competitive inhibitors, irrersible

Answer 2

• resembles substrate
• cant be overcome by increasing substrate
• binds active site
• lowers Vmax
• unchanged Km
• less efficacious

Question 3

noncompetitive inhibitors

Answer 3

• doesn’t resemble substrate
• cant by overcome by increasing substrate
• does not bind active site
• lowers Vmax
• does not affect Km
• less efficacious

Question 4

bioavailability (F)

Answer 4

fraction of drug that reaches the systemic circulation

- IV dose = 100%

Question 5

volume of distribution

Answer 5

volume occupied by total amount of drug in body relative to plasma concentration

Question 6

Vd equation

Answer 6

Vd = amount of drug/concentration (mg/mg/ml=ml)

Question 7

low Vd

Answer 7

stays in IV space, large/charged molecules, protein bound

Question 8

high Vd

Answer 8

in all tissues, small lipophilic molecules

Question 9

clearance

Answer 9

volume of drug clear per unit time

- can change based on organ function

Question 10

clearance equation

Answer 10

Cl = rate of elimination / drug concentration (mg/min / mg/ml)

Question 11

half life equation

Answer 11

t1/2 = Vd*0.693/Cl

Question 12

loading dose equation

Answer 12

Cp * Vd / F

Question 13

maintenance dose equation

Answer 13

Cp *CL * dose interval / F

Question 14

additive drug interaction

Answer 14

A + B = sum of effects

Question 15

permissive drug interactions

Answer 15

A is required for full B effects

Question 16

synergistic drug interactions

Answer 16

A + B = greater than sum of parts

Question 17

tachyphylactic drug interactions

Answer 17

acute decrease in response after administation

Question 18

zero order elimination

Answer 18

eliminated independent of concentration (constant amount)

Question 19

zero order drugs

Answer 19

phenytoin, ethanol, aspirin

Question 20

first order elimination

Answer 20

eliminated dependent on concentration (constant fraction)

Question 21

weak acids in urine

Answer 21

deprotonated form is ionized
will dissociate and stay trapped in urine
- in case of overdose, add base to remove H+ and keep drug in urine

Question 22

weak bases in urine

Answer 22

protonated is ionized

- in case of overdose, add acid to increase protonated form

Question 23

phase I drug metabolism

Answer 23

reduction, oxidation, hydrolysis with P450, yield slightly polar, water soluble metabolites

Question 24

phase II drug metabolism

Answer 24

conjugation (methylation, glucuronidation, acetylation, sulfation), very polar inactive metabolites
- slow acetylators have increased side effects

Question 25

efficacious drug

Answer 25

high Vmax, unrelated to potency

Question 26

potent drug

Answer 26

lowest dose that still causes symptoms | - unrelated to efficacy

Question 27

competitive antagonist curve

Answer 27

shift curve right, does not change efficacy, can be overcome

Question 28

noncompetitive antagonist curve

Answer 28

lowers curve (efficacy), doesn't change potency

Question 29

partial agonist

Answer 29

acts at the same site, lower efficacy, potency is independent

Question 30

sweat glands

Answer 30

are part of sympathetic pathway but are innervated by cholinergic fibers

Question 31

nicotinic receptors

Answer 31

ligand gated Na/K channels - Nn = autonomic - Nm = neuromuscular junction

Question 32

muscarinic receptors

Answer 32

G protein coupled receptors | - use Ach

Question 33

alpha 1 effects

Answer 33

increase vascular smooth muscle, pupillary dilator muscle contraction, intestinal and bladder contraction

Question 34

Gq pathway

Answer 34

receptor binding, phospholipase C converts PIP2 to IP# and DAG, activated PKC and increasing calcium

Question 35

Gs pathway

Answer 35

receptor binding, increase in adenylyl cyclase, increase cAMP, protein kinase A, increase in calcium and blocks myosin light chain

Question 36

Gi pathway

Answer 36

receptor binding, decrease in adenylyl cyclase, decrease cAMP, protein kinase A, decrease in calcium and activates myosin light chain

Question 37

tetrodotoxin

Answer 37

puffer fish toxin | - binds voltage gated sodium channels preventing depolarization

Question 38

ciguatoxin

Answer 38

reef fish toxin | - opens sodium channels causing depolarization