14.3 Pharmacology: Drugs and the GI system

Question 1

What is an example of an anti-emetic H1-R’ Antagonist?

Answer 1

Promethazine (Fenergen, sedative effect)

Question 2

Anti-emetic: Muscarinic receptor antagonist example

Answer 2

Hyoscine hydrobromide (sedative, crosses BBB)

Question 3

Anti-emetic:
Dopamine D2-R’ Antagonist examples (2)

Side effects?

Do these cross the BBB?

Answer 3

Metoclopramide, prochlorperazine

Parkinson’s like symptoms and drowsiness

All cross BBB except domperidone

Question 4

Anti-emetic:

Serotonin 5HT3 R’ Antagonists (& side effects)

Answer 4

Ondansetron (constipation, headaches)

Question 5

What is an example of a bulking agent? What is it used for?

Answer 5

Psyllium (laxative)

Question 6

What is an example of a fecal softener and lubricant? How does this work?

Answer 6

Docusate (detergent)

Question 7

What is an example of an osmotic laxative? How does this work?

Answer 7

Magnesium sulfate (epsom salts)

A saline laxative, cause stimulation by distention

Question 8

What is an example of a stimulant laxative? How does this work?

Answer 8

Senna (an irritant laxative)

Question 9

What is an example of an opioid?
How can it be used in the context of gastrointestinal problems?
How does it work?

Answer 9

Loperamide
An antidirrhoeal drug
Delays the passage of gut contents (doesn’t cross BBB, low abuse risk)

Question 10

What is an agent used for the treatment of flatulence?

Answer 10

A defoaming polymer- Simethicone