GI Flashcards
Referral/Red flags for constipation? (6)
- New or Worsening symptoms without explanation
- Tarry black / red/ bloody stools = (upper GI bleed?)
- Weight loss/loss of appetite (carcinoma?)
- Nausea and vomiting
- Weight gain + coarse hair + dry skin + lethargy (hypothyroidism?)
- Longer than:
7 days - children
14 days - adults
Which drugs can cause constipation? (10)
- Opioids
- Hyoscine
- Selective serotonin reuptake inhibitors (SSRIs) e.g. sertraline, citalopram, fluoxetine
- Tricyclic antidepressants e.g. amitriptyline
- Iron
- Chlorphenamine
- Bendroflumethazide
- Propranolol
- Aluminium containing antacids
- Verapamil
What is the first line treatment for constipation?
How long does it take to start seeing effects?
Lifestyle advice
Diet- increase fibre to 30g a day
Hydration
Exercise
3 to 5 days
What are drug treatments for constipation?
First line:
Bulk forming + hydration
e.g. Ispaghlua husk (bran) or methylcellulose (stool softener) or sterculia
2nd line:
Osmotic laxative
e.g. lactulose
3rd line:
Stimulant laxative
e.g. Senna or Bisacodyl or Docusate sodium or Glycerol (suppositories)
How do bulk forming laxatives work? How long to work?
Give some examples
They swell up in the gut to increase faecal mass so that peristalsis is stimulated.
usually begins within 24 hours but can 2-3 days for full effect
e.g. Ispaghula/ Fybogel (6 years)
Methylcellulose / Celevac (also stool softener)
Sterculia/ Normacol (6 years)
How do osmotic laxatives work? How long to work?
Give some examples
Maintain fluid volume in bowel
takes 2-3 days to work
Giving water with movicol reduces chance of dehydration sometimes seen with osmotic laxatives
E.g. Lactulose
Macrogol / Movicol
Magnesium salts
How do stimulant laxatives work? How long to work?
Give some examples
Stimulate peristalsis directly by increasing release of electrolytes and water from intestinal mucosa.
Effect within 6 hours/overnight or even faster within 1 hour with suppositories
e.g. Bisacodyl / Dulcolax (4 years) Senna (2 years) Sodium picosulfate (4 years) Glycerol suppositories (infant) Docusate sodium - has both stimulant and stool softening properties
How do stool softeners work? How long to work?
Give some examples
Increasing moisture in stools
24-48 hours
e.g.
methylcellulose
docusate sodium
What side effects can occur with Lactulose ?
Abdominal pain/cramps Diarrhoea Flatulence Nausea Vomiting
Especially at beginning of treatment
Uncommon
Electrolyte imbalance
Why is maintaining good hydration with bulk forming laxatives important?
Gastrointestinal discomfort & dehydration so
Risk of oesophageal an intestinal obstruction
How should you stop taking laxatives?
Reduce and stop one laxative at a time
- Stimulant
- Osmotic
What are some cautions with the continous use of laxatives?
Continuous use can cause the contents of the gut to be expelled such that no bowel movement occurs for 1-2 days so person wants to take more laxatives.
Leading to loss of muscular activity in bowel
Brand names of OTC laxatives ?
Ispagula husk - Fybogel
Sterculia - Normacol
Methylcellulose - Celevac
Lactulose
Macrogol - Movicol
Bisacodyl - Dulcolax (enteric coated so avoid antacids + milk at same time)
Docusate
Senna - Senokot
What causes constipation in pregnant women?
What can/can’t you use for treatment?
Especially in 3rd trimester - raised progesterone levels means gut muscles are more relaxed. Oral iron may contribute to the problem
- Lifestyle advice - diet and fibre
- Bulk forming okay in preg and breast feeding
- Osmotic -lactulose
AVOID stimulant - esp in 1st trimester and especially Senna
but could maybe use docusate or glycerol
What are the treatment options for children with constipation?
Diet alone is NOT 1st line
- Diet and Macrogol
- Stimulant
- Lactulose or softener e.g. docusate
