Laxatives Flashcards
5 types of laxative
- Bulk-forming laxatives: psyllium (Metamucil)
- Surfactant laxative: docusate sodium (Colace)
- Stimulant laxative: bisacodyl (Dulcolax)
- Osmotic laxative
- Misc: Chloride channel activator: lubiprostone (Amitiza)
how do we classify laxatives?
based on how fast you have a BM
when do we want to use laxatives?
When do we want to use laxatives?
- short term basis
- prevention of straining: post op, opioids, cardiac
When do we NOT want to give laxatives?
- acute abdomen - s/s of appendicitis, diverticulitis, UC –> bowel perf
- fecal impaction/obstruction –> bowel perf
- habitually to manage constipation
Constipation is more defined by stool ______ than _____
consistency, frequency
prototype for bulk forming laxative
Psyllium (Metamucil)
how does Psyllium (Metamucil) fxn?
Acts like dietary fiber --> Pull water into stool • increases mass • softens stool • feeds colonic bacteria • increases peristalsis • *works to decrease cholesterol
admin for Psyllium (Metamucil)
give w/ full glass of water
risk of _______ w/ Psyllium (Metamucil)
intestinal obstruction
Psyllium (Metamucil)- prevent or treat constipation?
preventative
- okay to use daily
onset of action for Psyllium (Metamucil)
1-3 days (III)
prototype for Surfactant Laxatives
docusate sodium (Colace)
how does docusate sodium (Colace) fxn?
Lower surface tension
- -> increase fluid in stool by inhibiting fluid absorption
- softens stool, causes secretion of water and electrolyte into the intestine
- site of action is small intestine and colon
(makes it easier to go- falls right out of your dooky hole)
indication for using ducosate sodium?
• post surgical, cardiac, postpartum: prevent straining
is ducosate sodium preventative or treatment for constipation?
preventative
admin for docusate sodium (Colace)
full glass of water
onset of docusate sodium (Colace)
1-3 days (III)
prototype for osmotic laxatives
polyethylene glycol (Miralax)
how do osmotic laxatives fxn?
Nonabsorbable compound
• pull water into intestinal lumen –> fecal mass swells and stimulates peristalsis
indication for low dose vs high dose osmotic laxatives
low dose: Used for chronic constipation, Daily use, PREVENTATIVE
high dose: Bowl Prep in high dose, TREATMENT
side effects of polyethylene glycol (Miralax) (low dose)
Nausea, abd. Bloating, cramping, flatulence
onset of osmotic laxatives: low vs high dose
low: 2-4 days
high: 2-6 hours
milk of magnesia is _______ laxative. It is contraindicated in _____ patients
osmotic
renal
considerations for high dose osmotic laxatives
- Risk of dehydration
- Not used in renal dysfunction or cardiac patients
- Deaths associated with use
lactulose is a ______ laxative
osmotic
lubiprostone (Amitiza) falls in what class of laxative?
misc!
how does lubiprostone (Amitiza) fxn?
Selective Chloride channel activator
• promotes the secretion of Cl rich fluid into the intestine
• enhances motility of small and large intestine
lubiprostone (Amitiza) onset
w/in 24 hours
indication for lubiprostone (Amitiza)
Irritable bowel syndrome, Chronic idiopathic constipation , Opioid induced constipation
lubiprostone (Amitiza)- preventative or treatment
preventative, daily use
side effects of lubiprostone (Amitiza)
nausea
admin of lubiprostone (Amitiza)
take w/ food and water
gotta have food when ur ready for lube
why does laxative abuse occur? explain the patho
• normal filling of bowel results in defecation reflex
◦ only a portion of bowel empties out during BM, then fills, and reflex to poop again
______
• with stimulant or osmotic laxative that clears the entire bowel, it takes a long time for bowel to refill and cause defecation reflex –> + bowel forgets to work due to being used to exogenous stimulation
