Common drugs in GORD/PUD

Question 1

What are the main receptors associated with a parietal cell?

Answer 1

Proton pump

H2 receptor

M3 receptor

CCK2 receptor

Prostaglandin receptor

Question 2

List four protective substances in the stomach

Answer 2

Mucus

Bicarbonate

Prostaglandins

Mucosal blood flow

Question 3

List four aggressive substances in the stomach

Answer 3

Acid

Pepsins

NSAIDs

H. pylori

Question 4

What is the role of antacids?

Answer 4

To neutralise acid produced in the stomach

Question 5

What is the role of alginates?

Answer 5

Increase viscosity of stomach content

Some form a “raft” to reduce symptoms of reflux

Question 6

Give examples of antacids

Answer 6

Sodium Bicarbonate

Magnesium and Aluminium salts

Gaviscon

Rennie

Simeticone

Question 7

Give an example of an alginate

Answer 7

Sodium alginate

Question 8

What is the side effect of aluminium?

Answer 8

Constipation

Question 9

What is the side of effect of magnesium?

Answer 9

Diarrhoea

Question 10

What do alginates and antacids interact with?

Answer 10

Some antibiotics , i.e. coprofloxacin, tetracycline

Enteric coated preperations

Question 11

What is the mechanism of action of sulcralfate?

Answer 11

Protect damaged mucosa by stimulating local production of prostaglandins and bicarbonate

Question 12

What are the infications of sucralfate?

Answer 12

Treatment of peptic ulceration

Prophylaxis of stress ulceration

Question 13

What are the side effects of sucralfate?

Answer 13

Constipation

Question 14

What does sucralfate interact with?

Answer 14

Enteral feeds - “bezoar” formation

Digoxin, antibiotics, phenytoin - reduced absorption

Question 15

What is the mechanism of action of misoprostol?

Answer 15

Prostaglandin analoge, i.e. prostaglandin receptor agonist

used in combination with NSAID, e.g. arthrotec

Question 16

What are the side effects of misoprostol?

Answer 16

Diarrhoea and abdominal pain

Question 17

What are the contraindications of misoprostol?

Answer 17

Pregnant women / Women of child-bearing age

Question 18

Give examples of gastric stimulants

Answer 18

Domperidone

Metoclopramide

Question 19

What is the mechanism of action of gastric stimulants?

Answer 19

Increases peristalisis in duodenum and jejunum, thought to be due to stimulation of muscarinic receptors in GIT

Question 20

Give examples of H2-receptor antagonists

Answer 20

Ranitidine

Nizatidine

Famotidine

Cimetidine

Question 21

What are H2-receptor antagonists mechanism of action?

Answer 21

Reversibly and competitively bind to H2-receptor

• suppresses gastric acid secretion
• inhibits gastrin and ACh-mediated acid secretion

Question 22

What are the indications of H2-receptor antagonists?

Answer 22

PUD
GORD symptoms

HIgh dose in ZE syndrome

Question 23

How are H2-receptor antagonists excreted?

Answer 23

Renal and hepatic excretion

- important to know in case of renal/hepatic impairment

Question 24

What are the side effects of H2-receptor antagonists?

Answer 24

Diarrhoea/constipation
Headache
Confusion
Hallucinations

Question 25

How does Cimetidine affect the cytochrome-p450 system?

Answer 25

Inhibits it

Question 26

Give examples of PPIs?

Answer 26

Omeprazole Lanzaprazole Pantoprazole Esomeprazole

Question 27

What are the indications of PPI?

Answer 27

PUD Prevention and treatment of NSAID induced ulceration Eradication of H.pylori (with Abx) Severe GORD symptoms Oesophagitis ZE syndrome Prevention of stress ulceration in critical care patients

Question 28

What are the side effects of PPI?

Answer 28

No obvious ones Rare: rash, headache, diarrhoea, nausea

Question 29

List any interactions of PPIs?

Answer 29

Omeprazole with clopidogrel

Question 30

What are some of the functions of prostaglandins?

Answer 30

Protection of gastric mucosa Platelet function Pain, inflamamtion and fever Renal homeostasis