Anti-diarrhoeals & Laxatives

Question 1

What opioid receptor agonists are used as anti-diarrhoeals?

Answer 1

Loperamide
Codeine
Morphine

Question 2

How does loperamide act as an anti-diarrhoeal?

Answer 2

Bind to μ receptors in the myenteric plexus

Decrease tone in longitudinal and circular smooth muscle
Reduce peristalsis but increase segmental contractions
Decrease colonic mass movements by suppressing gastrocolic reflex

Question 3

What are some side effects of opioid agonists when used as anti-diarrhoeals?

Answer 3

Paralytic ileus
Nausea and vomiting
Sedation
Addiction

Question 4

What is the constipating diet?

Answer 4

Indicated for those with long term loose stools - IBD, IBS, short bowel, side effect of drug

Bananas, white rice, white bread
Avoid caffeine, fizzy drinks and spicy food

Consider probiotics

Question 5

What types of medicine can be used for constipation?

Answer 5

Osmotic laxatives
Stimulant laxatives
Bulk forming laxatives
Stool softeners

Question 6

What are some examples of osmotic laxatives?

Answer 6

Lactulose
Movicol
Cosmocol

Question 7

How do osmotic laxatives treat constipation?

Answer 7

Increase the amount of water in the large bowel

Draw fluid in - lactulose
Retain fluid they came with - macrogols

Question 8

How do stimulant laxatives treat constipation?

Answer 8

Increase intestinal motility
Given orally or PR

Docusate sodium - stimulant and stool softener
Glycerin suppositories - rectal irritation and lubrication

Question 9

What are some examples of stimulant laxatives?

Answer 9

Bisacodyl
Sodium picosulphate
Senna
Docusate sodium

Question 10

How do stool softeners treat constipation?

Answer 10

Decrease surface tension of stool => breaking up

Increase penetration of fluid into stool

Question 11

What are some examples of stool softeners?

Answer 11

Docusate sodium
Glycerin suppository
Arachis oil
Liquid paraffin