Pharm of upper GI

Question 1

what is GORD?

Answer 1

gastro-oesophageal reflux disease (reflux of gastric contents in to oesophagus) leading to oesophagitis

Question 2

what is Barrett’s oesophagus?

Answer 2

Damage to epithelial cells can lead to pre-cancerous state

Question 3

what are 3 common causes of GORD?

Answer 3

Obesity
Pregnancy
Drug-induced

Question 4

what are 6 signs and symptoms of peptic ulceration? Give as many as you can (2 of them not relevant)

Answer 4

Epigastric pain 
hunger pain
night pain relieved by food/milk/antacids
waterbrash
nausea and vomiting
haematemesis

Question 5

what are the 2 most common causes of peptic ulceration (PU) and what are 2 tests for infection?

Answer 5

Helicobacter pylori
NSAIDs

Urea breath test - 13C urea
Biopsy for urease activity
H.pylori antigens / antibodies in blood, saliva, stools.

Question 6

Explain the C13 Urease breath test

Answer 6

H. Pylori survives in stomach by breaking down urea in food, creating ammonia that neutralises acid

Question 7

what are the secondary messengers for each receptor, and what can inhibit all pathways?

Answer 7

H2- cAMP
CCK2-Ca-dep
M3 - Ca-dep

PGs on PGR inhibits all three

Question 8

how do antacids work and give a couple of examples

Answer 8

raise pH
symptomatic relief
sodium bicarbonate
magnesium hydroxide

Question 9

what are alginates, give an example, and what do they do?

Answer 9

when combines with saliva forms a viscous foam
floats on the gastric contents forming a raft which protects the oesophagus during reflux.

e.g. gaviscon/peptec

Question 10

how do H2 antagonists work? Drug name example?

Answer 10

reduce gastric acid secretion

Cimetidine - inhibits cytochrome P450 and therefore the metabolism of other drugs, resulting in important drug interactions

Question 11

how do PPIs work? Example of a drug?

Answer 11

act via irreversible inhibition of the proton pump (H+/K+-ATPase)
omeprazole, pantoprazole, esomeprazole

Question 12

explain triple therapy and treatment of H. pylori. What are the 3 antibios available to use?

Answer 12

Triple Therapy for 1 week then PPI alone

Clarithromycin
Amoxicillin
Metronidazole

Question 13

what do coritcosteroids and NSAIDs block respectively?

Answer 13

PLA2

COX

Question 14

what’s the difference between COX-1 and COX-2?

Answer 14

COX-1 – physiological, gastric protection

COX-2 – pathological, inflammation

Question 15

what does misoprostol do?

Answer 15

• a stable PGE1 analogue, acts on prostanoid receptors to inhibit gastric H+ secretion.