13
Side Effects/Problems
b
Mechanism of Action
Bloating, flatulence, iron and calcium
malabsorption
Stool bulk ↑, colonic transit time ↓,
GI motility ↑
Bloating, flatulence
Mixed soluble and insoluble fiber, stool bulk ↑
Bloating, flatulence Stool bulking
Less bloating
Bloating, flatulence
Sweet taste, transient abdominal cramps,
flatulence, bloating
Nonabsorbable disaccharides metabolized
by colonic bacteria into acetic and other
short-chain fatty acids, which accelerate
colonic transit
Incontinence due to potency, bloating,
abdominal cramps
Osmotically ↑ intraluminal fluids
Rectal irritation, abdominal cramps Evacuation induced by local rectal
stimulation
Irritation
Incontinence, hypokalemia, abdominal
cramps
Similar to senna
(see Stimulants, Anthraquinones)
Malabsorption, abdominal cramps,
dehydration, melanosis coli
Electrolyte transport altered by
↑ intraluminal f luids, myenteric plexus
stimulated, motility ↑
Does not ↑ GI motility
Stool soening
Magnesium toxicity, dehydration,
abdominal cramps, incontinence
Fluid osmotically drawn into small-bowel
lumen, cholecystokinin stimulated, colon
transit time ↓
Avoid in renal failure
Lipid pneumonia, malabsorption
of fat-soluble vitamins, dehydration,
incontinence
Stool lubricated
Mechanical trauma Evacuation induced by distended colon,
mechanical lavage
Accumulated damage to rectal
mucosa, hyperphosphatemia,
mechanical trauma
Nausea, diarrhea, abdominal pain, bloating,
flatulence, headache
Intestinal secretion ↑,
chloride channel 2 activator
Diarrhea, abdominal pain, flatulence
Intestinal secretion ↑,
guanylate cyclase-C agonist
Abdominal pain, flatulence, nausea,
dizziness, diarrhea, hyperhidrosis
GI motility ↑, peripheral µ-antagonist
c
In clinical practice, senna and docusate sodium are commonly used in combination due to their
complementary mechanisms of action.
