Drugs and motility in GI tract - Constipation

Question 1

Give an example of a Lubricant used to treat constipation?

Answer 1

Liquid paraffin

Question 2

How does Liquid paraffin work?

Answer 2

lubricates the contents of the intestinal tract to promote bowel movement

Question 3

why must special care be taken when using liquid paraffin?

Answer 3

lubricant laxatives line the mucosal surface thus they might prevent the absorption of fat soluble vitamins and other nutrients

Question 4

Give two examples of Bulk-forming drugs used in the treatment of constipation?

Answer 4

Sterculia

Bran

Question 5

What is the mechanism of action of Sterculia and

Bran?

Answer 5

It increases the volume of non-absorbable food material in the colon

Question 6

What special care should be taken when using Sterculia and

Bran?

Answer 6

Adequate fluid intake should be provided to avoid dehydration and consequential worsening of constipation

Question 7

Give three examples of Intestinal Stimulants used to treat constipation?

Answer 7

Bisacodyl
Dantron
Phenolphthalein

Question 8

What is the mechanism of action of Bisacodyl,

Dantron, and Phenolphthalein?

Answer 8

Stimulate contraction of intestine to aid faecal expulsion.

Stimulation of cAMP, CCK, and VIP synthesis

Question 9

What special care should be taken when using Bisacodyl, Dantron, and Phenolphthalein?

Answer 9

Might cause abdominal cramps and they are not to be used if suspected intestinal obstruction

Question 10

Give two examples of Osmotic Laxatives that are used in the treatment of constipation

Answer 10

MgSO4

Lactulose

Question 11

What is the mechanism of action of MgSO4 and

Lactulose?

Answer 11

They are poorly absorbed solutes which remain in the GI tract and so promote the movement of water from the tissues into the lumen