gastroparesis

Question 1

Erythromycin

Answer 1

Binds motilin receptors in stomach + SI - stimulates contraction + improves gastric emptying

AE: diarrhea, N/V, abdominal cramps; rare: hepatitis, hypersensitivity rxn, arrhythmias

IV > PO, tolerance develops

Question 2

Domperidone

Answer 2

Blocks D2 receptors – increases duration of antral and duodenal contractions + inhibits fundal relaxation

AE: rashes, abdominal cramps (only in Canada)

Question 3

Metoclopramide

Answer 3

Accelerates gastric emptying
Peripheral: increases cholinergic activity, D2 receptor antagonist, direct effect on GI smooth muscle
Central: D2 receptor + serotonin receptor antagonist –> anti-emetic

AE: restlessness, drowsiness, fatigue, insomnia, drug interactions; BLACK BOX: tardive dykinesia

Don’t use in pts with pheochromocytoma, epilepsy