Laxative Medications –
Classification
1. Saline Osmotic – magnesium hydroxide (MOM)
sodium biphosphate (Fleet enema)
2. Stimulant – bisacodyl (Dulcolax)
senna (Senokot)
3. Bulk Forming – psyllium hydrophilic mucilloid (Metamucil)
4. Emollient/Lubricant/Stool Softener – mineral oil (Kondremul Plain)
docusate sodium (Colace)
5. Evacuant – polyethylene glycol elect. sol’n – (GoLYTELY)
- Saline Osmotics:
magnesium hydroxide (MOM)
sodium biphosphate (Fleet enema)
Action
Hyperosmolar salts pull water into colon, increase water in feces to increase bulk, which stimulates peristalsis (movemnt of fecal matter)
2. Stimulant (Irritant) laxatives:
bisacodyl (Dulcolax)
senna (Senokot)
Action
Increase peristalsis by irritating sensory nerve endings in intestinal mucosa
Results
Oral- 6-12 hrs, suppository- 15-60 min
Side effects
Abdominal cramps, weakness, reddish brown urine, diarrhea
3. Bulk Forming Laxatives
Psyllium hydrophilic mucilloid (Metamucil)
Action
Absorb water into intestines, increase bulk and peristalsis
Results – 8-12 hrs
Administration
Mix in glass of water or juice, stir, drink immediately, follow with 1 glass water
Side effects
Abdominal cramps
Excess laxative -diarrhea, nausea,vomiting, gas
4. Emollient (Stool Softener/Lubricant)
docusate sodium(Colace)
mineral oil (Kondremul Plain)
Action
¡Lowers surface tension
¡Promotes water accumulation in intestine
¡Emulsifies and lubricates feces for easier passage
Use
¡Prevents constipation
¡Reduces straining post surgery or myocardial infarction
Side effects
¡Abdominal cramping, nausea, vomiting, diarrhea
5. Evacuant Laxative
polyethylene glycol electrolyte solution(GoLYTELY)
Action – diarrhea that cleanses bowel in 4 hr
Side effects- diarrhea within 1 hr of admin.
Use – bowel cleansing before colonoscopy
(Off label in children – acute iron overdose)
Advantage – no electrolyte imbalance