Laxatives

a. action: moves stool; mechanism dependent on type of laxative

b. examples
i. lubricants moisten stool; mineral oil
ii. stool softeners allow water to penetrate stool; dioctyl sodium sulfosuccinate (Colace)
iii. bulk forming: increase bulk in intestine; psyllium hydrophilic mucilloid (Metamucil)
iv. colon irritant stimulates peristalsis; bisacodyl (Dulcolax)
v. saline cathartics increase osmotic pressure thereby absorbing fluid from bowel wall; milk of magnesia

c. use: to treat constipation

d. adverse reactions
i. gastric effects: nausea, cramping, diarrhea
ii. dependence with long-term use
iii. intestinal lubricants inhibit absorption of fat-soluble vitamins
iv. saline cathartics: dehydration, hypernatremia

e. contraindications:
i. GI obstruction
ii. suspected appendicitis
iii. megacolon
iv. abdominal pain
v. nausea

f. nursing interventions
i. monitor effects of medication
ii. teach client
• dietary considerations (increased fiber and fluid intake)
• maintain/increase activity level
• caution regarding overuse of laxatives
• mix bulk-forming laxatives with a glass of water and follow with another glass of water