IBS

Question 1

What are the classifications of IBS?

Answer 1

• IBS-C (>25% is Bristol type 1/2, <25% is Bristol type 6/7)
• IBS-D (>25% is Bristol type 6/7, <25% is Bristol type 1/2)
• IBS-mixed (>25% is Bristol type 1/2 & >25% is Bristol type 6/7)

Question 2

Rome Criteria for IBS?

Answer 2

Recurrent abd pain on average ≥1 day/week in the last 3m, a/w ≥2 of the following:
- related to defecation
- a/w change in frequency of stool
- a/w change in form of stool
+ sx onset ≥6m before diagnosis

Question 3

Diagnosis of IBS?

Answer 3

• abd pain/discomfort relieved by defecation OR
• altered bowel frequency or stool form

+ ≥2 of the following:
- change in how pt passes stools (straining, urgency, incomplete evacuation)
- abd bloating, distension, tension or hardness
- sx worsen after eating
- mucous stool

Question 4

Nonpharm management of IBS?

Answer 4

Dietary changes
- take regular meals, no rushing meals
- restrict caffeine to 3 cups/day
- reduce alcohol & carbonated drinks
- reduce ‘resistant starch’ intake
- low FODMAP diet (banana, gluten-free, meat & fish, lettuce etc)

Exercise

Question 5

What does FODMAP stand for?

Answer 5

fibre, oligosaccharides, disaccharides, monosaccharides, polyols

Question 6

What advice is to be given to IBS-D and IBS-C pts regarding eating fibres?

Answer 6

• IBS-D: discourage from eating insoluble fibre
• IBS-C: increase soluble fibre with increased water intake

Question 7

First line pharmacological tx for IBS? & examples

Answer 7

• anti-motility drugs for IBS-D (when nonpharm failed): loperamide > dhamotil (loperamide does not cross BBB), trimebutine
• laxatives for IBS-C (when nonpharm failed): PEG (NOT lactulose -> worsen sx), stimulant if PEG don’t work
• antispasmodics for abd pain & cramps: hyoscine butylbromide, mebeverine, dicyclomine, alverine

Question 8

If 1st line tx fails, what can be tried for IBS?

Answer 8

Antidepressants (low-dose)
- TCAs preferred (but avoid in IBS-C) (e.g. 5-10mg ON amitriptyline)
- SSRI if TCA fails

Antiflatulents (but no evidence): simethicone, dimethicone