GI Drugs MOA

Question 1

How does maropitant work

Answer 1

Acts on neurokinin receptor (NK) 1

Question 2

MOA metoclopramide

Answer 2

Sensitises Upper GI muscles to the effects of acetylcholine.

Centrally
antagonises Dopamine D2
Antagonises serotonin 5HT3
Agonist serotonin 5HT4

Question 3

MOA erythromycin

Answer 3

Mimics effects of motilin and 5-HT3
Stimulate migrating motility complexes and antegrade peristalsis

Question 4

Cisapride MOA

Answer 4

5-HT4 agonist enhances Ach at myenteric plexus
5-HT1 and 5-HT3 antagonist enteric cholinergic neurons
5-HT2 alpha receptor agonist on colonic smooth muscle.