antiemetics/ antinausea

Question 1

Ondansetron

Answer 1

5-HT3 receptor antagonist that blocks serotonin action on enterochromaffin cells on small intestine, vagal efferents, STN and CTZ

Question 2

Olanzapine

Answer 2

Dopamine receptor 2 antagonist that blocks dopamine action on CTZ, can induce weight gain through serotonin receptor blockade

Question 3

Aprepitant

Answer 3

NK-1 receptor antagonist that blocks substance P action on CTZ and vomiting center;

Question 4

Dronabinol

Answer 4

cannabinoid receptor 1 agonist that activates appetite center of brain and can have weak anti-emetic action

Question 5

Hyoscine (scopolamine)

Answer 5

muscarinic receptor antagonist that blocks cholinergic stimulation of STN and vestibular nuclei; lecture 6 slide 14 states hyoscine (scopolamine) prevents motion sickness by blocking Ach receptors in vestibular part of ear,

Question 6

Diphenhydramine

Answer 6

Histamine 1 receptor antagonist that blocks histaminergic stimulation of STN and vestibular nuclei