Constipation Flashcards
healthcare definition
<3/week
straining associated with defecation
hard dry stool
patient perception of constipation
small stool
feeling of incomplete evacuation
decreased stool frequency
patho
slower than normal movement thru the gi tract. Tonic contractions (stomach), peristaltic waves (intestines)
internal anal spincter relaxation (rectum)
secondary causes:
systemic
neuro
pshychological
- systemic: electrolyte imbalances, thyroid disorders, IBS
- neurological: autonomic neuropathy, MS, parkinsons, cerebrovascular accidents, dementia
- psychological: depression, eating disorders, situational stress
contributing meds
OPIATES *morphine and oxycodone* antacids anticholinergics antidepressents antihistamines benzodiazepines beta blockers calcium channel blockers diuretics iron supplements muscle relaxants statins
risk factors
age > 65
female
pregnancy and post birth
secondary causes
clinical presentation
complains: reduced stool frequency, straining, hard/dry stools, feeling of incomplete evacuation
additional symptoms: anorexia, headache, low back pain, abdominal discomfort, bloating, flatulence
complications: hemorrhoids, bleeding, rectal ulcers, anal fissures
rome criteria
2 or more of the following:
- less than 3 bowel movements / week
- straining during > 25% of defecations
sensation of incomplete evacuation in >25%
-sensation of anorectal obstruction / blockage for >25
- manual maneuvers to facilitate >25%
exclusions to self care
severe ab pain, distention, cramping, or unexplained flatulence
concomitant fever, nauseu, and or vomiting
unexplained changes in bowel habits (esp if weight loss)
blood in the stool or dark tarry stool or changes in stool character
symtoms persisting >2 weeks or recur over a period of 3+ months, or after dietary/lifestyle changes
daily laxitive use (not including fiber based therapy)
Age <2 years
conditions precluding laxatve self treatment (paraplegiz/ quadriplegiz, colostomy)
history of inflammatory bowel disease, anorexia
nonpharmacologic
diet and excersize
- increase fluid 2L / day
increase fiber (25g in women 38 for men)
fruits (prunes) vegetables, whole grains.
limit foods with little fiber content
- meats cheese and processed foods
effects seen in 3-5 days
how should you increase fiber?
slowly over 1-2 weeks
what is bowel retraining
it is heed the urge, allow sufficent toilet time
attempt upon waking or 30 minutes post meal
what are some daily fiber supplements
Inulin (fiberchoice, metamucil, clear and natural)
partiallly hydrolyzed guar gum (sunfiber)
powdered cellulose (unifiber)
wheat dextrin (benefiber)
pharmacologic laxative types
bulk forming hyperosmotic emollient lubricant saline stimulant
Bulk forming laxatives indiciation
RECOMMENDED CHOICE for most instances of constipation
- useful for patients on low fiber diets, post partum, older adults, patients w colostomies, IBS
propylaxis for those who should refrain from straining
bulk forming - MOA
dissolves or swells in the intestinal fluid -> forms emollient gel -> stimulates peristalsis -> facilitates passage of intestinal contents
Bulk forming - SAFETY
- CHOKING RISK - avoid if difficult studying, esopheal strictures, fluid restrictions ( heart failure)
- OBSTRUCTION, fecal impaction - avoid if palliative care, OPIOID-INDUCED constipation, intestinal ulcerations
- HYPERCALCEMIA – older adults, renal impairment
Bulk forming - TOLERABILITY
Abdominal cramping, flatulence
increased flatulence or risk of obstruction if recommended dose exceeded
Bulk forming - efficacy
Closely mimic the physiologic mechanism in promoting evacuation
Onset: 12-24 hours (may be delayed up to 72 hours)
Bulk forming - DI
Decreased absorption
- Physical binding of medications in GI tract
- Chelation with calcium-containing laxatives
- Oral tetracyclines,
quinolones
Separate administration by 2 HOURS
Hyperosmotic Laxatives - Indication
Polyethylene glycol (PEG) 3350 - short term treatment for occasional constipation for patiens 17+ years
Glycerin - lower bowel evacuation for patients of all ages
Hyperosmotic Laxatives - MOA
large, poorly absorbed ions that draw water into the colon or rectum via osmosis
Hyperosmotic Laxatives - Safety
PEG3350- consult pcp in renal disease and IBS
Glycerin: innappropriate for patients with rectal irritation
hypokalemia with chronic use
Hyperosmotic Laxatives - Tolerability
Peg 3350: bloating, abdominal discomfort, cramping, flatulence
diarrhea/excessive stool frequency with higher doses
Glycerin: rectal irritation
Hyperosmotic Laxatives - Efficacy
PEG 3350- onset 12-72 hours (up to 96 hours in some patients)
Glycerin - onset 15-30 minutes
Hyperosmotic Laxatives - DI
minimally absorbed - none sig
Emollient laxatives - stool softeners indication
prevention of straining and painful defecation
patients with anorectal disorders, severe hypertension, cardiovascular disease, recent surgery, postpartum women
prevention of opioid induced constipation in combination with a stimulant laxative
treatment of occasional constipation `
Emollient laxatives - MOA
anionic surfactant that softens fecal mass
- increases the wetting efficiency of intestinal fluid -> mixture of aq and fatty substances
Emollient laxatives - safety
weakness, sweating, muscle cramps, irregular heartbeat with excessive doses
Emollient laxatives - tolerability
diarrhea, mild cramping
Emollient laxatives - efficacy
onset 12 - 72 hours (up to 3-5 days in some patients)
Emollient laxatives - DI
minimally absorbed
increased systemic absorption of mineral oil - avoid combination
Emollient laxatives - examples of meds
docusate sodium
docusate calcium
Lubricant Laxatives - indication
prevention of straiing or painful defecation
USE IN SELF CARE STRONGLY DISCOURAGED DUE TO SAFER ALTERNATIVES
Lubricant Laxatives - MOA
softens fecal contents by coating stool and preventing colonic absorption of fecal water
Lubricant Laxatives - Safety
lipid pneumonia - avoid in patients < 6 years, older adults, pregnant, bedridden, difficulty swallowing
Lubricant Laxatives - Tolerability
abdominal cramps, diarrhea, nausea, vomiting, anal leakage with larger doses
Lubricant Laxatives - efficacy
onset 6-8 hours (oral) 5-15 minutes (rectal)
use is similar to emollient laxatives
Lubricant Laxatives - DI
Increased systemic absorption
- avoid combination with docusate products
decreased absorption of vitamins
- increased bleeding risk in patients taking warfarin
Lubricant Laxatives - product
Mineral oil - oral liquid or enema
Saline Laxatives - indication
Treatment of occasional constipation
Pre-operative bowel evacuation (e.g. colonoscopy)
Saline Laxatives - MOA
Ions that are retained in the intestinal wall
Draw in water via osmosis -> increased intraluminal pressure and intestinal motility
Saline Laxatives - Safety
Dehydration – avoid in patients who cannot tolerate fluid loss
Magnesium products – avoid in newborns, older adults, renal impairment
Sodium phosphate products – avoid in congestive heart failure, caution in renal impairment
Saline Laxatives - tolerability
Cramping, nausea, vomiting
Dehydration – consume 8 oz. water following administration of magnesium products
Saline Laxatives - Efficacy
Onset 30 min. – 6 hours (oral magnesium hydroxide)
Onset 30 min. – 3 hours (oral magnesium citrate, sodium phosphate)
Onset 2-15 min. (rectal magnesium citrate, sodium phosphate)
Saline Laxatives - DI
Oral anticoagulants, digoxin, chlorpromazine
Decreased absorption
Chelation with magnesium-containing laxatives
Oral tetracyclines, quinolones
Saline Laxatives - products
Magnesium citrate
magnesium hydroxide
sodium phosphate
magnesium sulfate
Stimulant Laxatives - indication
Pre-operative bowel evacuation (e.g. colonoscopy)
Prevention or treatment of opioid-induced constipation in combination with docusate
Stimulant Laxatives - MOA
Increase intestinal motility by local irritation of the mucosa or action on the intramural nerve plexus of intestinal smooth muscle
Increase secretion of water and electrolytes into the intestine
Stimulant Laxatives - safety
Severe cramping, electrolyte and fluid deficiencies, protein loss, malabsorption, hypokalemia, excessive loss of fluid during evacuation
Subject to overuse (patients with disordered eating, elderly, misconceptions about normal BM frequency)
Stimulant Laxatives - tolerability
Vomiting, nausea, diarrhea, severe cramping with excessive doses; red/violet/brown-colored urine (senna)
Stimulant Laxatives - efficacy
Onset 6-10 hours (up to 24 hours in some patients)
Onset 15-60 minutes (rectal bisacodyl)
Stimulant Laxatives - DI
Rapid erosion of enteric coating (bisacodyl)
Antacids, histamine2-receptor antagonists, proton pump inhibitors, milk
Separate administration by 1 hour
Stimulant Laxatives - products
senna
bisacodyl
castor oil
Special Populations Children Advanced Age Pregnancy Lactation
Children
Difficulty/delay in BMs 2+ weeks
See previous slides
< 2 years = direction of medical provider
Advanced Age
Avoid/use caution with mineral oil, saline and stimulant laxatives
Pregnancy
Bulk-forming laxatives, docusate, short-term senna or bisacodyl use
Avoid castor oil, mineral oil, saline laxatives
Lactation
Senna, bisacodyl, PEG 3550, docusate
Avoid castor oil, mineral oil
5 major counseling points
- Dietary, fluid, exercise changes effective for most
- Bulk-forming, PEG 3350 laxatives 1st line for most
- Self-treatment limited to 7 days
- Stop use and contact MD if rectal bleeding occurs
- Separate most laxatives from other meds by 2 hours
