(FETT) Anti-constipation Agents

GI Agents

ISPAGHULA HUSK

SENNA

Lactulose

Sodium docusate

Macrogols

• Bulk-forming laxatives are indigestible, not systemically absorbed.

• Soluble fibers increase water absorption in the intestinal lumen → stretching of the bowel wall → stimulation of peristalsis

• Bloating

• Diarrhea

• Worsening constipation

• Increase of osmotic pressure draws water into the intestinal lumen → stimulation of intestinal motility (peristalsis)

• Diarrhea Dehydration

• Magnesium salts: electrolyte abnormalities

• Flatulence, bloating

• Stimulation of epithelial cell secretion of electrolytes into the colonic lumen →

  • ↑ Secretion of fluid into the colon (with bisacodyl, this secretory activity is nitric oxide-mediated)

  • Myenteric neuronal depolarization → colon contractions (peristalsis)

• Stimulant laxative; primary active cathartic principles are the stereoisomeric glucosides, sennosides A and B. 

  
  

  Commonly thought that the stimulant laxatives induce defecation by stimulating propulsive peristaltic activity of the intestine through local irritation of the mucosa or through a more selective action on the intramural nerve plexus of intestinal smooth muscle, thus increasing motility. 

• More recent evidence shows that stimulant laxatives alter fluid and electrolyte absorption, producing net intestinal fluid accumulation and laxation. 

• Increases concentrations of cyclic 3′,5′-adenosine monophosphate (cAMP) in colonic mucosal cells and may alter the permeability of these cells and mediate active ion secretion, producing net fluid accumulation and laxative action. 

• Mainly promotes evacuation of the colon. 

• Diarrhea, which may result in severe water and potassium loss

• Melanosis coli (senna)

• Acute abdominal pain, nausea, vomiting, or other symptoms of appendicitis or undiagnosed abdominal pain. 

• Intestinal obstruction.

Abdominal discomfort, nausea, mild cramps, griping, faintness

Patients who require a low-galactose diet.

Gaseous distention, belching, flatulence,  borborygmi,  abdominal discomfort (e.g., cramping). 

Dehydration and hyponatremia in infants.