Anti-diarrhoeal agents

Question 1

What is an example of an anti-diarrhoeal

Answer 1

Loperamide (imodium)

• can also use opioids (morphine/ codeine)

Question 2

What are the indications for anti-diarrhoeal use

Answer 2

• Adult diarrhoea
• IBS
• Post bowel surgery

Question 3

What is the mechanism of action of anti-diarrhoeals

Answer 3

• acts on μ (mu) receptors in myenteric plexus
  = reduced ACh = reduced peristalsis + gut motility
• Allows for water reabsorption

Question 4

What are the side effects of anti-diarrhoeals

Answer 4

• constipation (abdo cramps, bloating, flatulence)
• dizziness, fatigue, headache
• PARALYTIC ILEUS
• Rash

Question 5

What are the contra-indications

Answer 5

• C. diff/ pseudomembranous colitis
• Ulcerative colitis
• dysentry
• hepatic impairment

Question 6

What is some useful information

Answer 6

• 4 mg loading dose then 2 mg after each bowel
  movement
• If diarrhoea doesn’t stop in 5 days → GP
• Advise good hydration + light meals
• May also need oral
  rehydration salts if severe