IRRITABLE BOWEL SYNDROME (IBS) Flashcards
What is the Epidemiology of IBS?
- Common bet ages 20-30
- *2 more in females than M
- Affects 10-20%, under-report
- *2 risk, 1st degree relatives
What is the Aetiology of IBS?
- Exact cause = Unknown
- Food intolerances e.g
Lactose/ Gluten are
precursors of IBS - No lesions present as gut
not damaged or diseased - Stress
-Post infective bowel
dysfunction, gut
hypersensitivity, altered
colonic motility and
heightened pain sensation all
implicated
What is the pathophysiology of IBS?
- Structurally = gut is normal
- IBS is a ‘functional’ GI disorder
- No detectable pathology using standard tests
- Blood tests/stool samples/colonoscopy may be used to rule out other
conditions
What are the symptoms of IBS?
- Abdominal cramping
*Diarrhoea/constipation/alternating - Flatulence, Bloating
- Urgency to defecate
- Acid indigestion
- Nausea, Lethargy
- Eating may worsen symptoms
- Passing mucus in stools
How do you Diagnose IBS?
- Abdominal pain present for at least 6 months
- Relieved by defecation, or:
- Increased/decreased bowel frequency or stool form
- Plus at least 2 of the following:
- Abdominal bloating/distension
- Altered stool passage (straining, urgency, incomplete evacuation)
- Worsened by eating
- Passing mucus
How do you Diagnose IBS in secondary care using the Rome IV criteria?
Abdominal pain 1 day per week in last 3 months
Symptoms began at least 6 months prior
Alongside >2 of the following:
* Related to defecation
* Change in stool frequency
* Change in stool form
Describe the Classifications of IBS using the Rome IV Criteria?
- IBS-C
>25% of stools are types 1/2, <25% are types 6/7 - IBS-D
>25% of stools are types 6/7, <25% are types 1/2 - IBS-M
>25% of stools are types 1/2 AND >25% of stools are types 6/7 - IBS-U
Person has IBS, but bowel habits can’t be categorised as above
What are the treatments of IBS?
- Antispasmodic drugs
- Antidepressants
- Laxatives
- Loperamide
- Linaclotide
What drug class is the Preferred treatment in IBS?
Direct acting smooth muscle relaxants
What are the 2 classifications of Antispasmodics?
- Antimuscarinics (anticholinergics)
- Smooth muscle relaxants
Give examples of direct acting smooth muscle relaxant drugs used to treat IBS, including their doses?
- Alverine Citrate 60-120mg up to TDS
- Mebeverine 135mg TDS (20 mins before food) or 200mg BD for MR preps
- Peppermint oil capsules, 1-2 caps up to TDS
Give examples of antimuscarinic drugs used to treat IBS, including their doses?
- Hyoscine butylbromide
- Dicycloverine
- C/I in intestinal obstruction or paralytic ileus
When can Anti-depressants be used in IBS?
-Use is unlicensed, for people with IBS pain
-People usually not responded to typical treatments
-Doses given are lower than you would see for mental health uses
Give examples of TCAs used in IBS and their doses?
Tricyclic antidepressants (TCA)
- Amitriptyline 10-30mg at night
- SSRI 2nd line (Sertraline, Citalopram, Fluoxetine)
Why should you counsel patients who take Anti-depressants for IBS?
- COUNSEL patients as they may be shocked when reading PIL
-Pain modulatory effects/peripheral effects on GI function
What drug class can be used in IBS-C?
Laxatives
- Dose should be titrated according to symptoms
What drug laxative should NOT be used and why?
- Lactulose
Lactulose can increase gas production and worsen symptoms
What Laxative should be avoided in prolonged use in IBS?
Stimulant Laxative
What drug class can be used in IBS-D?
Loperamide
Who can buy Loperamide in IBS?
P/GSL versions of Loperamide can be used for Acute
diarrhoea in IBS, but only for patients >18 years old
Must have been diagnosed with IBS
When should you not sell Loperamide but refer instead?
Only for attacks lasting up to 48 hours (refer if longer)
What is the maximum time Loperamide can be used for?
Can be used for 2 weeks maximum, as long as individual bouts are less
than 48 hours
What drug is used in patients with Moderate to severe IBS-C in adults?
Linaclotide
When should Linaclotide be used in IBS-C?
- Person must have had IBS-C for at least 12 months
- Should only be used if max tolerated doses of laxatives haven’t helped
