American Board of Internal Medicine (ABIM) Certification Practice Exam

Which of the following is a prokinetic agent approved by the FDA for treating gastroparesis?

1. Domperidone

2. Metoclopramide

3. Cisapride

4. Ondansetron

The correct answer is: Metoclopramide

Metoclopramide is a well-established prokinetic agent specifically approved by the FDA for the treatment of gastroparesis. Gastroparesis is a condition characterized by delayed gastric emptying, and metoclopramide helps increase the motility of the upper gastrointestinal tract, which aids in the movement of food from the stomach into the small intestine. It works by acting as both a dopamine receptor antagonist and a serotonergic agent in the gastrointestinal tract, enhancing gastric emptying and reducing nausea. In contrast, domperidone, while a prokinetic agent, is not approved by the FDA for use in the United States due to concerns about cardiac side effects. Cisapride is another prokinetic that was previously used but has been withdrawn from the market due to its potential to cause serious heart rhythm abnormalities. Ondansetron is an antiemetic that does not have prokinetic properties, as it primarily works by blocking serotonin receptors to reduce nausea and vomiting.