Proton Pump Inhibitors - Omeprazole

Question 1

What are PPIs used for?

Answer 1

PPIs are 1st line for
1) prevention of peptic ulcer disease and NSAID associated ulcers.

2) Symptom relief of dyspepsia and GORD
3) triple therapy for eradication of H.pylori

Question 2

How are PPIs used for eradication of H.pylori?

Answer 2

Triple therapy for 7 days.
- full dose PPI + amoxicillin 1g + clarithromycin 500mg

OR

• full dose PPI + metronidazole 400mg + clarithromycin 250mg

Question 3

What is the mechanism of action of PPIs?

Answer 3

Irreversibly inhibit H+/K+ATPase proton pumps in the gastric parietal cells.

Completely supresses gastric secretion so better than H2 blockers.

Question 4

What are the common side effects of PPIs?

Answer 4

• GI disturbance
• headache
• hypomagnesaemia with prolonged use
• increased risk of C.diff

Question 5

What are the warnings of PPI use?

Answer 5

• may disguise symptoms of gastric cancer
• when given at high dose for prolonged time - can increase risk of fractur in elderly
• use with caution in pt with osteoporosis

Question 6

What are the drug interactions of PPIs

Answer 6

• PPIs (especially Omepazole) reduces antiplatelet effect of clopidogrel (decreases its activation by cytochrome P450 enzymes.

Question 7

How do PPIs (especially omeprazole) interact with clopidogrel?

Answer 7

PPIs (omeprazole) reduces the antiplatelet effect of clopidogrel,

PPIs decrease its activation by P450 enzymes.

lansoprazole and pantoprazole are the preffered PPIs for use alongside clopidogrel.