Laxatives - Stool softener +Stimulant

Question 1

There are 4 basic layers of the GIT. Organise them with the closest layer to the lumen 1st:

1 - mucosa
2 - serosa
3 - muscularis externa also known as muscularis propria
4 - submucoas

Answer 1

1 - mucosa
4 - submucoas
3 - muscularis externa also known as muscularis propria
2 - serosa

Question 2

In the 3rd layer of the GIT is the muscularis externa, contains smooth muscle. There are 2 layers of smooth muscle, an inner circular layer and an outer longitudinal layer. Together these perform peristalsis. Which of these layers is responsible for stopping food move backwards, and which is responsible for moving food forward?

Answer 2

• stopping food moving backwards = INNER CIRCULAR LAYER
• moving food forward = OUTER LONGITUDINAL LAYER

Question 3

The 3rd layer of the GIT is the muscularis externa, containing an inner circular and an outer longitudinal layer os smooth muscle. This is separated by what?

1 - submucosal nerve plexus
2 - lamina propria
3 - myenteric nerve plexus
4 - muscularis mucosa

Answer 3

3 - myenteric nerve plexus

Question 4

Which of the following is NOT contained within the dense submucosal layer?

1 - arteries
2 - veins
3 - submucosal nerve plexus
4 - lamina propria

Answer 4

4 - lamina propria

Question 5

Which 2 of the following are the functions of the submucosa plexus contained within the submucosal layer of the GIT?

1 - peristalsis of the GIT
2 - control of blood vessels
3 - secretion of mucus
4 - GIT secretions

Answer 5

2 - control of blood vessels
4 - GIT secretions

Question 6

The mucosa contains 3 separate layers. Which of the following is NOT a layer of the mucosa?

1 - muscularis mucosa
2 - submucosal nerve plexus
3 - lamina propria
4 - epithelial layers

Answer 6

2 - submucosal nerve plexus

• muscularis mucosa = break up food
• lamina propria = blood and lymph vessels
• epithelial layers = absorbs and secretes mucus and GIT secretions

Question 7

According to NICE, diarrhoea is the abnormal passage of loose or liquid stools. Which 2 of the following are needed in a patient to be diagnosed with acute diarrhoea?

1 - >3 times/day daily and/or a volume of stool >200g/day
2 - >10 times/day and/or stool volume >500g/day
3 - <14 days in duration
4 - >14 days in duration

Answer 7

1 - >3 times/day daily and/or a volume of stool >200g/day

3 - <14 days in duration

• chronic diarrhoea is >4 weeks

Question 8

Which of the following are included in the definition of constipation?

1 - <3 bowel movements/wk
2 - excessive straining
3 - abdominal pain or bloating
4 - all of the above

Answer 8

4 - all of the above

Question 9

Which of the following are included in the definition of chronic constipation?

1 - <3 bowel movements/wk
2 - excessive straining
3 - abdominal pain or bloating
4 - symptoms present in 12 weeks of the last 6 months
5 - all of the above

Answer 9

5 - all of the above

Question 10

What is the stool softener and stimulant that we need to know?

1 - ispaghula husk
2 - senna
3 - glycerol suppositories
4 - docusate sodium

Answer 10

4 - docusate sodium

Question 11

How does docusate sodium soften stool and stimulate GI peristalsis (select 2)?

1 - contains synthetic dietary fibre that remains in stool and draws in H2O
2 - acts as a surfactant
3 - reduces fluid lost in the GIT from stool
4 - acts as an irritant to the GIT

Answer 11

2 - acts as a surfactant
- hydrophobic part remains in stool bound to lipids
hydrophilic part points out to water and draws it into the stool

4 - acts as an irritant to the GIT
- increases secretions into lumen, thus increasing volume and stretch and therefore peristalsis

Question 12

Which 2 of the following is docusate sodium indicated in the use of?

1 - diarrhoea
2 - chronic constipation
3 - adjunct in radiological procedures
4 - IBD

Answer 12

2 - chronic constipation
3 - adjunct in radiological procedures

Question 13

How is docusate sodium typically administered?

1 - orally
2 - IV
3 - suppository
4 - IM

Answer 13

1 - orally
- takes 1-2 days to be effective

3 - suppository
- effective in 20 minutes

Question 14

Which of the following are common adverse events of docusate sodium?

1 - abdominal cramps
2 - diarrhoea
3 - nausea
4 - rash
5 - melanosis coli (changes in pigmentation of colon)
6 - all of the above

Answer 14

5 - all of the above

Question 15

Docusate sodium is contra-indicated in which of the following?

1 - diarrhoea
2 - intestinal obstruction
3 - ileus
4 - diverticulitis

Answer 15

2 - intestinal obstruction