Lower GI Pharmacology

Question 1

What are some common side effects of anti-muscarinics?

Answer 1

Dry mouth, urinary retention, constipation

Question 2

What are H1-receptor antagonists (e.g. Cyclizine) used for?

Answer 2

Antiemetics

Question 3

Name three categories of antiemetics

Answer 3

H1-receptor antagonists, dopamine receptor antagonists, 5HT receptor antagonists

Question 4

Why does Orlistat often result in steatorrhea?

Answer 4

Pancreatic lipase inhibitor means that fats aren’t digested and absorbed, so come out in faeces

Question 5

What is the main negative consequence of using PPIs?

Answer 5

More susceptible to infection because stomach acid weaker, so weaker immune defence

Question 6

Which antibiotic is commonly used for traveller’s diarrhoea?

Answer 6

Ciprofloxacin

Question 7

What are opioids used for?

Answer 7

Diarrhoea relief (slow GI motility) or pain relief

Question 8

What does Loperamide do and how does it work?

Answer 8

. Opioid used for symptomatic diarrhoea relief
. Reduces release of ACh, which slows GI motility
. Promotes reabsorption of water for less watery stool
. Doesn’t penetrate BBB and has efficient enterohepatic recycling, so mostly retained in gut to take effect

Question 9

What is codeine used for? What is a common side effect?

Answer 9

Opioid used for analgesia, constipation is common side effect