Drugs and the Gut

Question 1

What two drugs are used for inhibiting gastric acid secretion?

Answer 1

H2- antagonists (ranitidine)

Proton pump inhibitors (omeprazole)

Question 2

How do H2- receptor antagonists work?

note lack of effectiveness (max acid suppresion 50%, need for mutliple doses)

Answer 2

They compete with histamine for binding site on parietal cells.
Increasing the dose won’t add to effect and short lasting (6-8 hours)
Tolerance can occur over time (tachyphylaxis)

Question 3

How do proton pump inhibitors work?

Answer 3

Irreversible blockage of proton pumps of parietal cells. Long lasting (up to one day, might need to take two doses)

Question 4

What is sulphasalzine?

Answer 4

5-ASA moelcules linked to sulphapyridine, colonic bacteria break it down, make it good to work on colon