Amboss ANTIEMETIC

Question 1

antiemetic groups?

Answer 1

Dopamine receptor antagonists;

Serotonin receptor antagonists
(5-HT3 antagonists);

Anticholinergic agents;

Antihistamines

Neurokinin receptor antagonists

Question 2

Dopamine receptor antagonists?3

Answer 2

Prochlorperazine, METOCLOPRAMIDE, Domperidone

Question 3

Metoclopramide. mechanism?

Answer 3

D2 receptor antagonist.

Question 4

metoclopramide. Where action in brains?

Answer 4

Central antiemetic effect at the area postrema.

Question 5

Metoclopramide. Peripheral GI effect?

Answer 5

Peripheral antiemetic effect in the gastrointestinal tract (prokinetic effect);

Question 6

Metoclopramide. What prokinetic effect?

Answer 6

incr. Gastric contractions (contractility)
incr. Duodenal and jejunal motility
incr. Resting tone of the lower esophageal sphincter
incr. LES tone

promotes gastric emptying

Question 7

Metoclopramide. effect on colon?

Answer 7

Does not influence colon transport time (no effect on colon motility)

Question 8

Metoclopramide. Together with decreased pylorus sphincter activity allows food to pass more quickly through the stomach and the small intestine

Answer 8

.

Question 9

Indications of metoclopramide?

Answer 9

Diabetic and postoperative gastroparesis, antiemetics, persistent GERD.
Hyperemesis gravidarum

Question 10

why metoclopramide for postsurgery gastroparesis?

Answer 10

due to prokinetic effect on stomach

Question 11

metoclopramide. GI adverse?

Answer 11

diarrhea, pain

Question 12

metoclopramide. neuro adverse?

Answer 12

Depression, anxiety
Fatigue
Drowsiness
Restlessness
!!!Lowering of seizure threshold

Overdose leads to reversible extrapyramidal syndrome (e.g., dystonia, parkinsonism, !!tardive dyskinesia, and akathisia).
Do not combine metoclopramide with antipsychotics because this increases the risk of dyskinesia!
Antidote: biperiden (anticholinergic agent)

Question 13

metoclopramide + antipsychotics?

Answer 13

Do not combine metoclopramide with antipsychotics because this increases the risk of dyskinesia!

Question 14

metoclopramide antidote for neuro adverse?

Answer 14

Antidote: biperiden (anticholinergic agent)

Question 15

metoclopramide has important interacton with what 2 medications?

Answer 15

digoxin and antidiabetic agents

Question 16

metoclopramide is contraindicated for 2 patients?

Answer 16

Contraindicated in patients with suspected small bowel obstruction;

Parkinson disease (because metoclop. blocks D2 receptors)

Question 17

Serotonin receptor antagonists (5-HT3 antagonists) agents?

Answer 17

Ondansetron
Granisetron
Dolasetron
Palonosetron

Question 18

ondrastenon mechanism?

Answer 18

5-HT3 antagonist

Question 19

ondrastenon location of effect in brains?

Answer 19

Strong central antiemetic effect at the area postrema

Question 20

ondrastenon peripheral inhibition?

Answer 20

Peripheral antiemetic effect via inhibition of the vagus nerve (decr. vagal stimulation)

Question 21

ondrastenon - STRONG CENTRAL-ACTING ANTIEMETIC

Answer 21

.

Question 22

Ondansetron is commonly used for generalized nausea.

Answer 22

.

Question 23

Serotonin receptor antagonists

(5-HT3 antagonists) indications?

Answer 23

postoperative nausrea and vomiting (PONV) and in patients undergoing chemotherapy/radiation.

Question 24

Serotonin receptor antagonists

(5-HT3 antagonists) adverse?

Answer 24

headache, constipation,
!!!!QT interval prolongation –> tdp
increase in liver enzymes
!!SEROTONIN syndrome

Question 25

Anticholinergic agents?

Answer 25

Scopolamine

Question 26

scopolamine mechnaism?

Answer 26

Nonspecific muscarinic antagonist
Central antiemetic effect at the area postrema and on the vestibular system
Peripheral antiemetic effect via inhibition of the vagus nerve

Question 27

scopolamine indications?

Answer 27

Motion sickness, vestibular-induced nausea, and vomiting

Question 28

scopolamine adverse?

Answer 28

Anticholinergic side effects: dry mouth, mydriasis, tachycardia, urinary retention
Antidote: physostigmine (cholinesterase inhibitor)

Question 29

Neurokinin receptor antagonists. agents?

Answer 29

Aprepitant

Fosaprepitant

Question 30

Aprepitant mechanism?

Answer 30

NK1 antagonist: Inhibition of NK1 receptors in the solitary nucleus → central antiemetic effect

Substance P antagonist: Additional inhibition of substance P-induced vomiting due to antagonism

Question 31

aprepitant, location of action in the brain?

Answer 31

solitary nucleus –> central antiemetic effect

Question 32

Aprepitant. indication?

Answer 32

Chemotherapy-induced nausea and vomiting (CINV) prophylaxis.

Question 33

Aprepitant. adverse?

Answer 33

Gastrointestinal: diarrhea
Fatigue
Hypersensitivity reactions
Infusion site reactions
Increased levels of other drugs  due to weak CYP3A4 enzyme inhibition

Question 34

Antihistamines. agents?

Answer 34

Meclizine
Dimenhydrinate
Diphenhydramine
Doxylamine
Promethazine

Question 35

antihistamines, mechanism?

Answer 35

H1 antagonist

Central antiemetic effect at the area postrema and VESTIBULAR system

Question 36

antihistamines indications?

Answer 36

Strong sedative

Nausea and vomiting due to vestibular causes

Hyperemesis gravidarum (also see antiemetics during pregnancy)

Question 37

antihistamines adverse?

Answer 37

Antihistamine effects: drowsiness and confusion

Anticholinergic side effects: dry mouth, dilated pupils, blurred vision, reduced bowel sounds, and urinary retention (antidote: physostigmine)