Laxatives

Question 1

Indications

Answer 1

1. Constipation
2. Mild chronic diarrhoea (bulk-forming)
3. Impaction (osmotic and stimulant)
4. Bowel preparation (osmotic)
5. Hepatic encephalopathy

Question 2

Mechanism of action

Answer 2

Bulk-forming
- Contain hydrophillic substance not digested by gut. Draws water into the stool

Osmotic
- Contains osmotically active substance that hold water in the stool

Stimulant:
- Increase water and electrolyte secretion from the colonic mucosa, increasing colonic volume and triggering peristalsis

Question 3

Adverse effects

Answer 3

Bulk-forming - mild discomfort/flatulence

Osmotic - flatulence, cramps, nausea

Stimulant - Cramps

Question 4

Warnings

Answer 4

Bulk-forming - should not be used in bowel obstruction, faecal impaction or ileus

Osmotic - contraindicated in intestinal obstruction, heart failure, ascites, electrolyte disturbances

Stimulant - contraindicated in intestinal obstruction. Rectal preparations should be avoided in anal fissure

Question 5

Interactions

Answer 5

Bulk-forming: none
Osmotic: none
Stimulants: none

Question 6

Prescription

Answer 6

Prescribed on regular section of drug chart.

Question 7

Administration

Answer 7

Bulk-forming: usually powder or granules to be dissolved

Osmotic - oral solution

PO

Question 8

Communication

Answer 8

Bulk-forming - explain that works as a fibre supplement

Osomotic - softens stool, making it easier to pass

Stimulant - will help the stool to pass.

Question 9

Monitoring

Answer 9

Stool chart