Constipation

Question 1

What can laxative abuse lead to?

Answer 1

• hypokalaemia

Question 2

What are examples of bulk forming laxatives?

Answer 2

• Ispaghula husk.
• Methylcellulose.
• Sterculia

Question 3

When would bulk forming laxatives be beneficial?

Answer 3

• If stools are small and hard and fibre cannot be increased in the diet

Question 4

What are examples of osmotic laxatives?

Answer 4

• Lactulose.
• Macrogols (polyethylene glycols).
• Phosphate and sodium citrate enemas

Question 5

How do osmotic laxatives work?

Answer 5

• Increase amount of fluid in large bowel

Question 6

What are examples of stimulant laxatives?

Answer 6

• Senna
• Bisacodyl and sodium picosulfate
• Docusate - reduces tension of the stool so water can penetrate and soften it

Question 7

When should stimulant laxatives be avoided?

Answer 7

• In intestinal obstruction

Question 8

How would you manage short duration constipation?

Answer 8

• first line - bulk forming laxative
• second line - if stools remain hard, switch to osmotic laxative
• third line - if stools are soft but still difficult to pass, stimulant laxative

Question 9

How would you treat opioid-induced constipation?

Answer 9

• osmotic laxative and stimulant laxative
• AVOID bulk forming laxative
• If response to laxatives inadequate - Maloxegol
• can also use methylnaltrexone bromide

Question 10

How do you treat faecal impaction in patients with HARD STOOLS?

Answer 10

• high dose of oral macrogol

Question 11

How do you treat faecal impaction in patients with SOFT STOOLS or if macrogol hasn’t worked?

Answer 11

• Start oral stimulant laxative (can be added onto prev treatment)
• If ineffective - bisacodyl

Question 12

How do you treat chronic constipation?

Answer 12

• bulk forming laxative + good hydration
• If stools remain hard - add/change to osmotic laxative (e.g. macrogol)
• If 2 laxatives have been tried for 6 months and it still isn’t helping - prucalopride

Question 13

How would you go about reducing laxatives if the patient is on multiple?

Answer 13

• one at a time

- try to start with the stimulant laxative

Question 14

How do you treat constipation in pregnancy?

Answer 14

• 1st line - diet control
• 2nd line - bulk forming laxative
• docusate sodium and glycerol suppositories can also be used
• avoid senna if possible
• stimulant laxatives are more effective but avoid due to side effects

Question 15

How do you treat constipation in children?

Answer 15

• first line - diet (increase fibre) + macrogol
• if response inadequate - stimulant laxative
• if stools remain hard - lactulose or docusate

Question 16

How do you treat faecal impaction in kids?

Answer 16

• macrogol

- if still present after 2 weeks - stimulant laxative