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*
*Abnormally infrequent and difficult passage offeces through the lower GI tract
*Symptom, not a disease
*Disorder of movement through the colonand/or rectum
*Can be caused by a variety of diseasesor drugs
*
*Constipation is generally defined as infrequent and/or
unsatisfactory defecation fewer than 3 times per week.
*Patients may define constipation as passing hard stools
or straining, incomplete or painful defecation.
Epidemiology
2-27% of the population has constipation
Constipation affects twice as many women
as men
Constipation is more prevalent in non-White
persons than in White persons (non-
White:White ratio range 1.11--2.89)
Causes of constipation
Diet
Lack of exercise
Age
Irregular bowel habits
Drug induced
Disease States/Conditions
Spasam of sigmoid colon
Dysfunction of myenteric plexus
* 1. Exercise - Fibre in the diet -
Fluid Intake
No evidence that increased exercise is beneficial in
severe constipation
Aim for 25-30g fibre/day
Unless dehydrated, increasing fluid does not relieve
chronic constipation and may increase the risk of fluid
overload eg heart or renal failure
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
*Bulk forming
*Emollient
*Hyperosmotic
*Saline
*Stimulant
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
1. Bulk forming
*High fiber
*Absorbs water to increase bulk
*Distends bowel to initiate reflex bowel activity
Examples:
*psyllium (Metamucil)
*methylcellulose (Citrucel)
*polycarbophil
Improve stool consistency and frequency with regular
use
Ensure good fluid intake to prevent faecal
impaction
Onset of action 2-3 days
Side Effects may include bloating, flatulence,
distension
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
2. Emollient
*Stool softeners and lubricants
*Promote more water and fat in the stools
*Lubricate the fecal material and intestinalwalls
Examples:
*Stool softeners: docusate salts (Colace, Surfak)
*Lubricants: mineral oil
*Stool softener may take days to become
effective.
*They should not be taken together with mineral
oil because of the potential for absorption of the
mineral oil.
*Lubricant laxatives include Mineral oil and
glycerin suppositories.
* They facilitate the passage of hard stools.
*Mineral oil should be taken orally in an upright
position to avoid its aspiration and potential for
lipid or lipoid pneumonia.
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
3. Hyperosmotic
*Increase fecal water content
*Result: bowel distention, increased peristalsis,and evacuation
Examples:
*polyethylene glycol (GoLYTELY)
*sorbitol
*glycerin
*lactulose (Chronulac)
*PEG powder for solution is available as a
prescription and also an over-the-counter
laxative.
*Lactulose is a semisynthetic disaccharide sugar
that also acts as an osmotic laxative. It is a
product that cannot be hydrolyzed by intestinal
enzymes. Oral doses are degraded in the colon
by colonic bacteria into lactic, formic, and
acetic acids. This increases osmotic pressure,
thereby accumulating fluid, distending the
colon, creating a soft stool, and causing
defecation.
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
Saline
*Increase osmotic pressure within the intestinaltract, causing more water to enter theintestines
*Result: bowel distention, increased peristalsis,and evacuation
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
Saline laxative; saline cathartic; examples:
*magnesium sulfate (Epsom salts)
*magnesium hydroxide (MOM)
*magnesium citrate
*sodium phosphate (Fleet Phospho-Soda, Fleetenema)
*Saline cathartics are nonabsorbable salts
(anions and cations) that hold water in the
intestine by osmosis and distend the bowel.
*increasing intestinal activity and producing
defecation in a few hours.
*Electrolyte solutions containing polyethylene
glycol (PEG) are used as colonic lavage solutions
to prepare the gut for radiologic or endoscopic
procedures.
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
4. Stimulant
*Increases peristalsis via intestinal nervestimulation
Examples:
*castor oil
*senna
*cascara
*bisacodyl
*Senna is a widely used stimulant laxative.
* Its active ingredient is a group of sennosides,
a natural complex of anthraquinone glycosides.
*Taken orally, it causes evacuation of the
bowels within 8 to 10 hours.
*It also causes water and electrolyte secretion
into the bowel.
*In combination products with a docusate-
containing stool softener, it is useful in treating
opioid-induced constipation.
*Bisacodyl, available as suppositories and enteric-
coated tablets, is a potent stimulant of the colon.
*It acts directly on nerve fibers in the mucosa of the
colon.
*Adverse effects include abdominal cramps and the
potential for atonic colon with prolonged use.
*.
*Antacids should not be taken at the same
time as the enteric-coated tablets. The
antacid would cause the enteric coating
to dissolve prematurely in the stomach,
resulting in stomach irritation and pain.
*The same adverse effects could be
expected with milk, H2-receptor
antagonists, and PPIs
*Castor oil is broken down in the small
intestine to ricinoleic acid, which is very
irritating to the gut, and promptly increases
peristalsis.
*It should be avoided by pregnant patients,
because it may stimulate uterine
contractions.
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
*Bulk forming
*Impaction
*Fluid overload
*Emollient
*Skin rashes
*Decreased absorption of vitamins
*Hyperosmotic
*Abdominal bloating
*Rectal irritation
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
* Saline
*Magnesium toxicity (with renal insufficiency)
*Cramping
*Diarrhea
*Increased thirst
* Stimulant
*Nutrient malabsorption
*Skin rashes
*Gastric irritation
*Rectal irritation
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
*All laxatives can cause electrolyteimbalances!
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
*Obtain a thorough history of presentingsymptoms, elimination patterns, andallergies
*Assess fluid and electrolytes beforeinitiating therapy
*Patients should not take a laxative orcathartic if they are experiencing nausea,vomiting, and/or abdominal pain
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
*A healthy, high-fiber diet and increased
fluid intake should be encouraged as an
alternative to laxative use
*Long-term use of laxatives often results in
decreased bowel tone and may lead to
dependency
*All laxative tablets should be swallowed
whole, not crushed or chewed, especially
if enteric coated
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
*Patients should take all laxative tablets with6 to 8 ounces of water
*Patients should take bulk-forming laxativesas directed by the manufacturer with at least240 mL (8 ounces) of water
Mosby items and derived items ©
2005, 2002 by Mosby, Inc.
*
*Bisacodyl and cascara sagrada should begiven with water due to interactions withmilk, antacids, and H2 blockers
*Patients should contact their
physician if they experience severe
abdominal pain, muscle weakness,
cramps, and/or dizziness, which may
indicate possible fluid or electrolyte
loss