Le38.Antiulcer Drugs

Question 1

What is the normal regiment an individual is put on if they are diagnosed with an ulcer?

Answer 1

1. Put on either an H2 receptor blocker or a proton pump blocker.
2. Also put on antibiotic regimen (i.e. Clarithromycin) to eradicate Helicobacter pylori, which helps prevent ulcer recurrence

Question 2

What are the two major drugs used as H2 receptor blockers in tx of GI ulcers? Why isn’t Cimetidine used frequently anymore?

Answer 2

Ranitidine (Zantac) & Famotidine (Pepcid) are the major H2 receptor blockers. Cimetidine is no longer used as frequently due to CYP3A4 inhibition leading to increased [warfarin, theophylline, phenytoin & diazepam]

Question 3

What are drugs with the suffix ‘-prazole’ used for?

Answer 3

-prazoles are proton pump inhibitors and are used to tx GI ulcers

Question 4

While proton pump inhibitors, such as Esomeprazole (nexium) & Omeprazole (Prilosec), are 90-100% more powerful than H2 blockers, they have what adverse drug reactions?

Answer 4

Proton pump inhibitors inhibit CYP3A4 leading to the accumulation of warfarin, phenytoin, theophylline & diazepam.

Question 5

How does metoclopramide reduce acid production?

Answer 5

Metoclopramide is a prokinetic agent that speeds up the movement of food from the stomach to the small intestine by stimulating release of actylcholine.

Question 6

In addition to its prokinetic affects, what other benefit does metoclopramide have?

Answer 6

Metoclopramide has drug induced anti-nausea activity b/c of it’s dopamine 2 receptor and seretonin (5HT-3) blockades. Note: not effective against motion sickness b/c doesn’t have anti-muscarinic activity.

Question 7

What is sucralfate (carafate) used for? MOA?

Answer 7

sucralfate is a crater filling agent that is used in GI ulcer and GERD tx. Sucralfate is a cytoprotective agent that lays a protective layer over the surface of a gastric or duodenal ulcer.