Irritable Bowel Syndrome

Question 1

How many people are affected by IBS?

Answer 1

10-20%

More common in North American women and Asian men

Question 2

How many patients that have IBS seek medical care?

Answer 2

15% seek medical care

Question 3

What is the brain-gut axis?

Answer 3

It is the connection between the brain and the gut.

Emotional instability can translate into GI instability via serotonin

Question 4

What happens to the brain-gut axis in patients with IBS?

Answer 4

They seem to over react to various stimuli (stress, diet, certain activity)

Question 5

What are some symptoms associated with IBS?

Answer 5

More than 6 months of duration

Symptoms:
Pain/spasms

Bloating/fullness

urgency

constipation <—–>diarrhea (cycle between the two)

Mucous in the stool, but no bleeding

Question 6

What are the different types of IBS?

Answer 6

IBS-D (primarly diarrhea)

IBS-C (primarily constipation)

IBS-mixed (cycle between diarrhea and constipation, hard to treat with usual agents due to “bipolar” nature of condition)

Question 7

What are some othe conditions that are similar to IBS?

Answer 7

Inflammatory Bowel Disease

Glucose intolerance

Drug-indiced

Lactose intolerance

Colorectal Cancer

Question 8

What are some non-pharmacological treatment options in IBS?

Answer 8

Dietary fiber (it could be an irritant)

Reduce fatty foods

Avoid offending foods (FODMAPs)

Question 9

What are FODMAP foods?

Answer 9

These are foods that IBS patients should avoid in their diet

Fermentable

Oligosaccharides

Disaccharides

Monosaccharides

AND

Polyols (sugar alcohols)

Question 10

What is the mechanism of action for Beano/Lactaid?

Answer 10

They contain alpha-d-galactosidase which helps breakdown complex carbohydrates in food (beans, vegetables, and whole grains)

This reduced the burden on the GI tract

Not for IBS though

Question 11

What are some pharmacogical agents used in IBS?

Answer 11

1. Bulk-forming agents
2. Smooth Muscle Relaxants
3. Anti-diarrheals
4. Laxatives
5. Peppermint Oil
6. Antidepressants
7. Linaclotide
8. Eluxadoline
9. Probiotics
10. Anti-cholinergics

Question 12

What is the efficacy of bulk-forming agents in IBS?

Answer 12

Psyllium is now reccomended for IBS-C (2-4 tbsps per day with fluids)

PEG-3350 has less evidence

Bulk-forming agents may help with IBS-D

Question 13

What is the efficacy of smooth muscle relaxants in IBS?

Answer 13

Create less spasm/better co-ordinations

Work best if used regularly

Try in IBS-D and IBS-C

ex. pinaverium (calcium channel antagonist) and trimebutine (opiate receptor agonist)

Question 14

What is the efficacy of anti-diarrheals in IBS?

Answer 14

Used in IBS-D and some limited used in IBS-mixed (when stool is more watery)

Decrease in diarrhea, but not much help for pain

Can be used for years safely (chronic therapy is common in IBS-D)

ex. loperamide 2-4mg up to QID

Question 15

What is a good strategy for controlling seemingly “uncontrollable” bowel movements in IBS with loperamide?

Answer 15

Take 2-4mg of loperamide approximately 45 min before leaving home

Question 16

What is the safety of long-term use of loperamide?

Answer 16

Indefinite dosing with loperamide is safe as long as you avoid constipation (unlikely to develop dependence), but it is not preferred. Loperamide is a rescue drug, patients should be on agents that are intended for chronic use

Question 17

Can loperamide be used safely in IBS-C?

Answer 17

No, loperamide will only worsen constipation by slowing down GI motility further

Only use loperamide in IBS-D and IBS-mixed when stool is watery

Question 18

What are some good therapeutic options for IBS-C?

Answer 18

Prevention: Psyllium, Inulin, and docusate

Acute treatment: senna

Question 19

What is the efficacy of peppermint oil in IBS?

Answer 19

It is mildly effective as a smooth muscle relaxer (broad spectrum works fine for both IBS-D, IBS-C, and IBS-mixed)

About 60% of patients benefit from the use of anti-spasmodics like peppermint oil

Question 20

What is the efficacy of antidepressants in IBS?

Answer 20

TCAs are effective in reducing pain and diarrhea from IBS-D (slowing of GI motility)

SSRIs do not control IBS-D symptoms (can actually worsen diarrhea if patient has IBS-D)

Question 21

What are some agents that take advantage of serotonin receptors in the GI tract to help treat IBS?

Answer 21

Alosetron: a 5 HT3 receptor antagonist (good for IBS-D)

Tegaserod: a 5-HT4 partial agonist (good for IBS-C)

Question 22

Review slide 38 to examine therapeutic options for IBS-D and IBS-C?

Question 23

What is the efficacy of linaclotide in IBS?

Answer 23

This agent is indicated for IBS-C

It acts locally (low side effects) and low oral bioavailability

Can cause diarrhea (preferable for patients with IBS-C

Question 24

What is the efficacy of eluxadoline in IBS?

Answer 24

It is a mu-opioid receptor agonist

It is indicated for IBS-D (will slow down GI motility)

Question 25

What is the efficacy of probiotics in IBS?

Answer 25

More than half (64%) of patients reported benefit over no benefit

It does not hurt to try, use agents that list IBS as an indication on the package

Question 26

What is the efficacy of anti-cholinergics (Bentylol) in IBS?

Answer 26

Not first line for IBS-D

They are less effective and have more side effects

Not the preferred agent (not endorsed by pharmacists or other HCPs)