Constipation Flashcards
Constipation
Hard/infrequent stools, excess strain, prolonged effort, sense of incomplete evacuation, unsuccessful defecation
Laxatives are used to ease or stimulate via softening, increasing volume, hastening passage, and facilitating evacuation from the rectum.
Laxative Effect
Production of soft, formed stool over 1 or more days. Slow and mild
Catharsis
Prompt evacuation of the bowel. Fast and intense
Normal
Wide range. 2-3 times/day to 2-3 times/week
Non-pharmacologic treatment
Increased fiber, fluids, and exercise
Laxative avoidance
Undiagnosed ab pain, n/v, cramps, or other s/s appendicitis
Acute surgical abdomen
Fecal impaction or bowel obstruction: risk perforating
Habitual use
Bulk Forming Laxatives Group 3 (slowest)
IND: constipation and dietary fiber supplement. Long term treatment with diverticulosis and IBS. Symptomatic relief in diarrhea
MOA: Mimic fiber, absorbs water in intestines to increase fecal mass, promoting peristalsis and reduces transit time
BOX: NONE
CONTRA: Fecal impaction, GI obstruction
ADRs: Take with full glass of water or juice. Rare but without fluids, can cause a GI obstruction or impaction
M/E: NONE
Psyllium: packets/powder and wafers
Methylcellulose: tabs or powder
Polycarbophil: tabs
Docusate
(surfactant Laxative, group 3)
IND: Stool softener, relief of occasional constipation. off label for ear wax impaction
MOA: Reduces surface tension of oil/water interface. Enhances incorporation of water and fat. Dawn dish soap.
BOX: NONE
CONTRA: NONE
ADRs: Throat irritation in liquid form only
M/E: NONE
Stimulant Laxatives
IND: Opioid constipation
MOA: stimulate motility and increase water and electrolytes in lumen
BOX: NONE
CONTRA: NONE
ADRs: Senna: yellow/brown/pink discoloration of urine
M/E: NONE
Bisacodyl: tabs. group 2
Bisacodyl suppositories: super group 1
Senna: group 2
Castor oil: group 1. Rarely used. Last line
Magnesium Citrate
Osmotic
IND: Constipation
MOA: Poorly absorbed salt that draws water into the intestinal lumen. 300 mL bottle = dose
BOX: NONE
CONTRA: NONE
ADRs: Hypermagnesemia, especially with chronic treatment. Dehydration.
M/E: Caution in renal impairment: magnesium accumulation
Polyethylene Glycol
Miralax, osmotic laxative
IND: constipation, bowel preparation before colonoscopy (combined with docalax)
MOA: Water retention in stool. Non absorbable material that holds water. Softens and swells fecal mass
BOX: NONE
CONTRA: Known or suspected bowel obstruction
ADRs: Nausea/bloating/cramping/flatulence. Dehydration.
M/E: NONE
Lactulose
Osmotic Laxative
IND: Constipation, hepatic encephalopathy
MOA: Draws water into lumen. Also decreases blood ammonia levels
BOX: NONE
CONTRA: NONE
ADRs: Dehydration, hypokalemia, hypernatremia
M/E: NONE
Lubiprostone
IND: chronic constipation and IBSC. Opioid induced constipation. More of a last line and more expensive
MOA: Cl channel activator: increases intestinal fluid secretion and improves fecal transit. Bypasses anti-secretory effect of opioids.
BOX: NONE
CONTRA: Known or suspected GI obstruction d/t risk of perforation
ADRs: GI disturbances
M/E: Hepatic adjustment needed
Naloxegol
IND: Opioid induced constipation MOA: mu-opioid receptor antagonist BOX: NONE CONTRA: Known or suspected GI obstruction. Concomitant use with strong CYP 3A4 inhibitors ADRs: GI disturbances M/E: NONE
Naldemedine
IND: Opioid induced constipation
MOA: mu-receptor antagonist. Decreases contipating effects of opioids
BOX: NONE
CONTRA: Known or suspected GI obstruction
ADRs: GI disturbances
M/E: NONE
