Chapter 26 Laxatives and Antidiarrheals

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Laxative Classifications Stimulant Saline Bulk-forming Lubricant  Stool softeners  Suppositories Lactulose Enemas

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Stimulant Laxatives Action  Chemical irritation  Increase motility of the GI tract  Increase secretion of water into large and small intestine  Example: bisacodyl

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Saline Laxatives Increase osmotic pressure within the intestinal tract  Cause more water to enter the intestines  Result in:  Bowel distention, increased peristalsis, and evacuation (continues)

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Saline Laxatives Contain salt Unpleasant taste Systemically absorbed Result in:  Poor client compliance  Risk for dehydration  Risk for congestive heart failure (continued)

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Bulk-Forming Laxatives Safest form  Absorbs water to increase bulk  Distends bowel to initiate reflex bowel activity  Not systemically absorbed  High fiber  Natural or semisynthetic  Examples: psyllium hydrophilic muciloid (Metamucil), methylcellulose (Citrucel), and polycarbophil (Fibercon) (continues)

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Bulk-Forming Laxatives Must be followed with a large amount of fluid  If chewed or taken in dry powder form, these agents can cause esophageal obstruction and/or fecal impaction. (continued)

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Lubricant Laxatives Oils lubricate the fecal material and intestinal walls, thereby promoting fecal passage:  Prevent fat-soluble vitamins from being absorbed Popular lubricant  Mineral oil (liquid petroleum)  Not digested or absorbed

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Stool Softeners Detergent-like drugs:  Permit mixing of fats and fluids with the fecal mass  Stool becomes softer and is passed much easier  Takes several days to work Example: docusate salts (Colace and Surfak)

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Suppositories Usually in a wax base Administered rectally Absorbed systemically Available containing stimulant drugs  Glycerin  Absorbs water from tissues, creating more mass  Bisacodyl  Induces peristaltic contraction by direct stimulation of sensory nerves

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Lactulose Laxatives Two monosaccharides that are not digested or absorbed Digested in the colon by bacteria to form acids substances  Acid substances cause water to be drawn into the colon

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved GoLYTELY Polyethylene glycol (electrolyte solution and salt)  Must consume 4 liters within 3 hours  Causes a large volume of water to be retained in the colon  Acts within one hour  Produces a diarrheal state

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Enemas Hyperosmotics  Solution contain salts (e.g., Fleet enema)  Administered rectally and cause a laxative effect by osmotically drawing fluid into the colon to initiate defecation

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Long-Term Use Long-term use of laxatives often results in decreased bowel tone and may lead to dependency. Encourage  A healthy, high-fiber diet  Increased fluid intake

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Adsorbents Most commonly used Claylike materials administered in a tablet or liquid suspension form after each loose bowel movement Bind to the causative bacteria or toxin, and are eliminated through the stool Little scientific proof that they work  Examples: kaolin-pectin, attapulgite (Kaopectate)

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Antidiarrheals Reduce GI motility Opium is a narcotic.  Decreases bowel motility and rectal spasms  Depresses the CNS; monitor closely  Decreases transit time through the bowel; more time for water and electrolytes to be absorbed Paregoric is an opium tincture.  May cause physical dependence (continues)

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Antidiarrheals Loperarmide HCl (Imodium)  Made from chemicals related to meperidine, a narcotic Diphenoxylate HCl and atropine sulfate (Lomotil)  Narcotic and anticholinergic drug  Reduces GI motility (continued)

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Anticholinergics Decrease intestinal muscle tone and peristalsis of GI tract Result: slows the movement of fecal matter through the GI tract  Example: belladonna alkaloids (Donnatal)

Copyright 2007 Thomson Delmar Learning, a division of Thomson Learning Inc. All rights reserved Nursing Implications Monitor for therapeutic effect