Table 4.
Medications used to treat constipation
| Type | Agent | Mechanism |
|---|---|---|
| Bulking | Psyllium (Metamucil) | Increases stool bulk and intestinal motility, shortens transit time |
| Methylcellulose (Citrucel) | Same as above | |
| Polycarbophil (FiberCon) | Same as above | |
| Docusate sodium (Colace) | Facilitates mixture of stool fat and water, softens stool | |
| Osmotic | Lactulose | Osmotically active nonabsorbable sugars pull fluid into the gut |
| Sorbitol | Same as above | |
| Polyethylene glycol (Golytely, Miralax) | Same as above | |
| Stimulants | Bisacodyl (Dulcolax) | Stimulates the myenteric plexus, increasing intestinal motility |
| Anthraquinones (Peri-Colace) | Same as above | |
| Senna (Senokot, Ex-lax) | Same as above | |
| Magnesium (milk of magnesia, magnesium citrate) | Shortens colonic transit time | |
| Glycerin suppository | Local rectal stimulation | |
| Enemas | Tap water | Colonic distention prompts defecation |
| Soap suds | Same as above, bowel wall irritant | |
| Monophosphate (Fleets) | Same as above, osmotic effect in small intestine, stimulates peristalsis |