Vertigo, Hearing Loss & N/V

Question 1

emesis location

Answer 1

CEC in lateral reticular formation of midbrain, adjacent to CTZ, area postrema and solitary tract nucleus

Question 2

receptor types in CTZ

Answer 2

5HT-3, D2, opioids

Question 3

receptor types in STN

Answer 3

encephalin, H, ACh, 5-HT3

Question 4

antihistaminergics & antichoinergics

Answer 4

meclizine, diphenhydramine, promethazine, scopolamine

Question 5

which drugs block H1 and M1

Answer 5

meclizine, diphenhydramine, promethazine

Question 6

which drug blocks M1 only

Answer 6

scopolamine

Question 7

AE of meclizine & diphenhydramine

Answer 7

drowsiness, dizziness, asthenia, weakness & confusion

∙ Meclizine has ↑in women

Question 8

AE of promethazine

Answer 8

drowsiness/sedation, fatal respiratory depression < 2 y/o. BBW if by INJECTION

Question 9

AE of scopolamine

Answer 9

xerostomia, drowsiness, ocular effects after touching patch & rubbing eye

Question 10

metabolism of the Anti-H and anti-M

Answer 10

heaptic (meclizine is CYP2D6 dominant)

Question 11

clinical utility for anti-H and anti-M

Answer 11

short term treatment of vertigo

Question 12

benzodiazepine used for anticipatory n/v

Answer 12

diazepam

Question 13

moa of diazepam

Answer 13

change in receptor activity & shift dose curve for GABA binding to left, ↑potency but NOT efficacy

Question 14

corticosteroids for n/v

Answer 14

dexamethasone, methylprednisone

Question 15

MOA of corticosteroids

Answer 15

unknown effect, presumably via steroid receptors in STN

Question 16

D2 antagonists for n/v

Answer 16

prochlorperazine, chlorpromazine

Question 17

d2 antagonists MOA

Answer 17

d2 receptor antagonism in CTZ, also posses anti-H and anti-M activities

Question 18

AE of d2 antagonists

Answer 18

chronic use at risk for BM suppression, risk for QT prolongation and torsade de pointes, co-admin with antipsychotics may ↑CNS effects

Question 19

metabolism of D2 antagonists

Answer 19

extensive hepatic

Question 20

clinical utility for D2 antagonists

Answer 20

“general purpose” n/v

Question 21

5HT3 antagonists

Answer 21

dolasetron, granisetron, ondansetron

Question 22

moa of 5HT3 antagonists

Answer 22

Antagonize 5-HT¬3 receptors in CTZ & solitary tract nucleus (STN)

Question 23

AE of 5HT3 antagonists

Answer 23

hypersensitivity reactions, QT prolongation, headache, constipation & diarrhea (MC)

Question 24

metabolism of 5HT3 antagonists

Answer 24

M: hepatic – CYP interactions

∙ dose adjust ONLY for ondansetron

Question 25

clinical utility for 5HT3 antagonists

Answer 25

Use for idiopathic n/v and post-operative n/v prophylaxis; often with corticosteroid

Question 26

substance P/NK1 antagonists

Answer 26

aprepitant, fosaprepitant

Question 27

MOA of aprepitant

Answer 27

Central action (solitary tract) essential, some contribution from peripheral effects

Question 28

AE of aprepitant

Answer 28

headache, constipation & diarrhea

Question 29

DDI of aprepitant

Answer 29

numerous, CYP

Question 30

Metabolism of aprepitant

Answer 30

xtensive hepatic (CYP) metabolism & 3A4 inhibitor

Question 31

ototoxics

Answer 31

aminoglycosides, cisplatin, loop diuretics

Question 32

MOA of toxicity of aminoglycosides

Answer 32

cell death of hair cells via caspase dependent & independent mechanism (JNK pathway releases cyt C)

Question 33

reversible agent for aminoglycoside toxicity

Answer 33

if reversible, give N-acetylcysteine

Question 34

moa of toxicity of cytotoxics

Answer 34

irreversible, enter outer hair cells and result in cell death via caspase-dependent mechanism only

Question 35

moa of toxicity of loop diuretics

Answer 35

fluid imbalance in production and maintenance of endolymph, usually temporary