Drugs

Question 1

Warfarin

Answer 1

stops carboxylation of coagulating factors

TI = 1, CYP2C9

Question 2

Diazepam

Answer 2

positive allosteric modulator of GABAa channel, TI = 100, N-dealkylation via CYP2C19, makes 2 intermediates –> long lasting

Question 3

Ondasentron (Zofran)

Answer 3

competitive inhibitor 5-HT3, treats nausea and vomiting by cancer chemo

Question 4

Benzodiazepine

Answer 4

(azepam, azolam) binds a-gamma site on GABAa to increase channel opening (positive allosteric modulator)
-treat anxiety, sleep and reduce muscle spasms

Question 5

Zolpidem (Ambien)

Answer 5

not a benzo, binds to specific benzo binding site, positive allosteric modulation, produce sleep

Question 6

Penicillin

Answer 6

blocks open GABAa channels –> seizures, uncompetitive inhibitor (convulsant)

Question 7

Strychnine

Answer 7

competitive inhibitor of glycine receptors –> excessive spasticity

Question 8

Tetanus toxin

Answer 8

blocks glycine release –> excessive spasticity

Question 9

Hyperekplexia

Answer 9

a subunits of glycine receptors mutated –> can’t bind glycine –> familiar startle disease

Question 10

Memantine (Namenda)

Answer 10

tx Alzheimer’s, open NMDA blocker (uncompetitive)

Question 11

Midazolam

Answer 11

benzo, hydroxylation cyp rxn

Question 12

Propranolol

Answer 12

beta blocker, hydroxylation cyp rxn

Question 13

cimetidine

Answer 13

H2 releases acid, competitive inhibitor of H2 w histamine, S-oxidation, blocks all CYPS except CYP2E1, good for ulcerative condition/heartburn

Question 14

diphenhydramine

Answer 14

benadryl, tx mild allergic rxns, comp. inhibitor of histamine at H1

Question 15

methylxanthine

Answer 15

caffeine/theophylline, competitive inhibitors of adenosine at low dose, phosphodiesterase inhibitor at high dose (increase cAMP)

• N-dealkylation
• CYP1A2

Question 16

adenosine

Answer 16

generally inhibits cellular function

Question 17

how does complementary shape affect antagonism

Answer 17

1. characteristic of competitive inhibition
2. makes for a tight fit
3. tighter fit = more selective drug

Question 18

acetominophen

Answer 18

analgesic/antipyretic, inhibits COX, sulfation OR glucuronidation

Question 19

albuterol

Answer 19

asthma tx, B2 receptor agonist, sulfation

Question 20

isoniazid

Answer 20

TB tx, inhibits mycolic acid synthesis, acetylation

Question 21

ibuprofen

Answer 21

NSAID, pain reliever and antiinflammatory, inhibits COX-1 and COX-2, CYP2C9

Question 22

Celecoxib

Answer 22

pain reliever, antiinflamatory, COX2, CYP2C9 selective for pain

Question 23

Gingko tea

Answer 23

induce CYP2C19, CYP 2C9, 3A4

Question 24

Echinacea

Answer 24

inhibit CYP1A2, induce 3A4

Question 25

St. John’s Wort

Answer 25

induce 3A4 (can increase metabolism of oral contraceptives), 2C9, 2C19 and 2E1

Question 26

clopidogrel

Answer 26

plavix, needs to be activated, anti-platelet, CYP2C19

Question 27

tacrilomus

Answer 27

immunosuppressant post transplant, low bioavailability, CYP3A5

Question 28

thiopurine drugs

Answer 28

need to be activated, problems with elimination, lower dose when TMPT doesn’t work