GI Pharmacology

Question 1

What are defensive and aggressive factors for gastric mucosa?

Answer 1

Defensive:
Cell replication and restitution
Mucous membrane barrier
High vascular supply

Aggressive:
Acid
H pylori
Drugs - NSAIDs

Question 2

What drugs are used for peptic disorders?

Answer 2

Antacids
Alginates
Histamine receptor antagonists
PPI

Question 3

What are some examples of H2RA?

Answer 3

Cimetidine, ranitidine

Nizatidine, famotidine

Question 4

Describe pharmacokinetics of histamine antagonists (peptic things)

Answer 4

Short half life => bd dosage

Causes hypochlorhydria
Doesn’t fully get rid of acid bc other receptors can be activated

Question 5

What are some examples of PPIs?

Answer 5

Omeprazole, lansoprazole
Rabeprazole, pantoprazole
Esomeprazole

Question 6

What is the action of PPIs?

Answer 6

Acts on active pumps
Taken when long term achlorhydria is required
Delayed action as not all pumps are active all the time

Question 7

Describe treatment for oesophagitis

Answer 7

Principles: control of symptoms and healing of oesophagitis

Lifestyle changes
Antacids/alginates
Histamine antagonists
PPIs

Question 8

Describe treatment for peptic ulcers

Answer 8

Stop NSAIDs
Histamine antagonists or PPIs for 6 wks
Get rid of H pylori

Question 9

How is H pylori gotten rid of?

Answer 9

2 abx with full acid block using a PPI

Eg clarithromycin, amoxicillin and lansoprazole