constipation Flashcards
common in these 3
women
pregnancy
elderly
what is it
defecation that is unsatisfactory because of infreq stools, difficult stool passage, seemingly incomplete defection
red flags - malignancy? bowel disorder?
- new onset, esp if >50
- anaemia, abdominal pain, weight loss, blood in stool
- review drug if caused by drug
advice for all pt with constipation
- increase dietary fibre (whole grains, fruit, veg)
- do this gradually to minimise flatulence and bloating
- effects may be seen in a few days, but may take as long as 4 weeks
- have fruits high in fibre and sorbitol
- adequate fluid intake will help soften stool and make it easier to pass
- this can be difficult in frail and elderly
true or false - avoid fruits that are high in sorbitol and fruit juices high in sorbitol if you have constipation
FALSE
e.g. apples, apricots, avocados, cherries, peaches, plums, prunes
These can help prevent and treat constipation
laxative abuse can lead to which electrolyte disturbance?
hypokalaemia
name 4 bulk forming laxatives
bran
isphagula husk
methyl cellulose
sterculia
this bulk forming laxative also acts as a stool softener
methylcellulose
onset of action for bulk forming laxatives
up to 72 hours
bulk forming laxatives can exacerbate the following symptoms
flatulence, bloating, cramping
(hence why when you counsel pt to increase fibre intake, you advice them to do this gradually)
is it important to advice pt to drink enough water when theyre on bulk forming laxatives because…
avoids intestinal obstruction
name 5 stimulant laxatives
- bisacodyl
- sodium picosulfate
- senna
- co-danthramer
- co-danthrusate
co-danthramer and co-danthrusate are what kind of laxatives?
stimulant
how to stimulant laxatives work and what is a common SE
increase intestinal motility, peristalsis
often cause abdominal cramps
avoid stimulant laxatives if …
intestinal obstruction
use of co-danthamer and co-danthrusate
only used in palliative care/terminally ill because of the potential carcinogenecity and genotoxicity
this laxative is believed to act as a stimulant and faecal softener
docusate
glycerol suppositories act as ..
lubricant and rectal stimulant due to its mild irritant action
how do faecal softeners work
decreasing surface tension and increasing penetration of intestinal fluid into faecal mass
these two laxatives have faecal softening properties
docusate (stimulant and softener)
glycerol (lubricant and rectal stimulant)
what laxative class would enemas containing arachnis oil fall into and why?
faecal softeners
they lubricate and soften impacted faeces to promote bowel movement
Liquid paraffin has been used as a lubricant. However, use with caution because of adverse effects e.g.
anal seepage
risk of granulomatous disease of GIY
lipid pnuemonia on aspiration
how do osmotic laxatives work
increase amount of water in large bowel by draining fluid from body into bowel or retaining the fluid they were adminsitered with
explain why lactulose is useful in hepatic encephalopathy
- not absorbed from the GIT
- produces osmotic diarrhoea of low faecal pH and discourages proliferation of ammonia producing organisms
name 2 osmotic laxatives
macrogol
lactulose
ensure macrogol is taken with sufficient fluid to ..
reduce dehydration
name two other drugs that are used in constipation
linaclotide
prucalopride
MOA lincalotide and when is it used
guanylate cyclase-C receptor agonist
licensed for treatment of moderate to severe IBS associated with constipation
increases intestinal fluid secretion and transit
decreases visceral pain
prucalopride MOA and use
selective 5HT3 receptor agonist
has pro kinetic properties (promotes movement in GIT)
licensed for chronic constipation in adults when other laxatives have failed to provide adequate response
are bowel cleansing preparations used for constipation
no
when are bowel cleansing preparations used
before colonic surgery, colonoscopy or radiological examination to ensure bowel is free of solid contents
