Laxatives Flashcards
3 examples of stimulant laxatives
Sodium picosulfate
Bisacodyl
Senna
How long does it take stimulant laxatives to work
6-12 hours
What patients cannot use stimulant laxatives
Those with intestinal obstruction
Mechanism of stimulant laxatives
Stimulate colonic nerves
Give 2 examples of bulk forming laxatives
Isphagula husk
Methylcellulose
Which type of laxatives are save in pregnancy
Bulk forming laxatives
How long does it take bulk forming laxatives to work
12-36 hours
Who cannot use bulk forming laxatives
Those with intestinal obstruction or faecal impaction
What’s the mechanism of action of bulk forming laxatives
Increase frequency, weight and consistency of stools
What is an example of a faecal softener
Docusate sodium
How long does it take faecal softeners to work
48 hrs
Who cannot/ should not use faecal softeners
Those with haemorrhoids or anal fissures
What’s the mechanism of action of faecal softeners
Reduces surface tension
Increases intestinal fluids into faecal mass
What are 3 examples of osmotic laxatives
Sodium citrate
Lactulose
Macrogols
How long does it take osmotic laxatives to work
48 hours +
What’s the mechanism of action of osmotic laxatives
Retains fluid in bowels by osmosis and changes water distribution in faeces to soften bowels
What is used for chronic constipation in which other laxatives have failed
Prucalopride
What’s the mechanism of prucalopride
Interacts with 5HT4 receptors in GI tract to stimulate mobility via releasing acetylcholine —> muscle contraction
