Drugs Used to Treat Constipation and Diarrhea Chapter 35 Drugs Used to Treat Constipation and Diarrhea Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Chapter 35 Lesson 35.1 Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Objectives State the underlying causes of constipation Explain the meaning of “normal” bowel habits Cite nine causes of diarrhea Describe medical conditions in which laxatives should not be used Identify electrolytes that should be monitored whenever prolonged or severe diarrhea is present Describe nursing assessments needed to evaluate the patient’s state of hydration when suffering from either constipation or dehydration Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Constipation Definition Chronic constipation Symptom-based disorder of unsatisfactory defecation characterized by infrequent stools, difficult stool passage, or both Chronic constipation Symptoms present for at least 3 months “Normal” bowel habits vary Daily bowel movement not necessary As long as patient’s health is good and stool not hardened or impacted, this is acceptable Occasional constipation is not detrimental to a person’s health, but may cause general discomfort, abdominal fullness, anorexia, or anxiety. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Causes of Constipation Improper diet Too little fluid intake Lack of exercise—sedentary habits Failure to respond to normal defecation impulses Muscular weakness of the colon Diseases such as anemia and hypothyroidism Frequent use of constipating medicines Tumors of the bowel or pressure from tumors Diseases of the rectum Diets that have too little residue (lacking fruits and vegetables or high in constipating foods) and too little fluid may result in constipation. Examples of medications causing constipation: morphine, codeine, anticholinergic agents. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Diarrhea Definition Considered a symptom, not a disease Increase in the frequency or fluid content of bowel movements Considered a symptom, not a disease Chronic diarrhea may indicate disease of the stomach or intestine Complications from severe or prolonged diarrhea Dehydration, electrolyte depletion, exhaustion Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Causes of Diarrhea Intestinal infections Spicy or fatty foods Enzyme deficiencies Excessive use of laxatives Drug therapy Emotional stress Hyperthyroidism Inflammatory bowel disease Surgical bypass of the intestine Antibiotics may cause diarrhea because they kill off normal flora in the bowel. Antacids containing magnesium may also cause diarrhea. Inflammatory bowel diseases include diverticulitis, ulcerative colitis, gastroenteritis, Crohn’s disease. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Treatment of Altered Elimination Constipation High-fiber diet, adequate hydration, exercise Avoid use of laxatives Avoid laxatives in patients with: Severe pain or discomfort Fever, nausea and vomiting Pre-existing conditions – DM, abdominal surgery Taking medications that cause constipation Laxative abusers Previous use of laxative without success Prescribed medications that cause constipation: iron, aluminum antacids, antispasmodics, muscle relaxants. Do not administer laxatives to patients with undiagnosed abdominal pain, or inflammation of the GI tract. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Treatment of Altered Elimination (cont’d) Diarrhea Treatment depends on specific cause of diarrhea Indication of disease of stomach, small or large intestine Psychogenic Symptom of cancer of the colon or rectum Diarrhea can be chronic, mild, or severe. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Nursing Assessment and Health Promotion Obtain history, medications, activity and exercise, elimination patterns, nutritional history, basic assessment, bowel sounds, vital signs; review laboratory reports Monitor electrolytes in prolonged diarrhea Monitor hydration Promote health Teach proper handwashing Teach drug adverse effects Monitor hydration by evaluating volume of intake, urine output, skin turgor, moisturization of mucous membranes, and daily weight. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Chapter 35 Lesson 35.2 Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Objectives Identify the indications for use, method of action, and onset of action for stimulant laxatives, saline laxatives, lubricant or emollient laxatives, bulk-forming laxatives, and fecal softeners. State the differences between locally acting and systemically acting antidiarrheal agents. Cite conditions that generally respond favorably to antidiarrheal agents. Review medications studied to date and prepare a list of those that may cause diarrhea. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Drug Class: Laxatives Actions Stimulant and osmotic laxatives Subclassified according to action Stimulant and osmotic laxatives Action: directly on intestines; cause irritation that promotes peristalsis and evacuation Osmotic laxatives Action: hypertonic compounds draw water into the intestines from surrounding tissues, distending bowel and causing peristalsis Common adverse effects: excessive bowel stimulation, diarrhea. Serious adverse effects: abdominal tenderness, pain, bleeding, vomiting, diarrhea, increasing abdominal girth. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Stimulant and Osmotic Laxatives Drugs Stimulants: bisacodyl (Correctol, Dulcolax, Modane), sennosides A&B (Ex-Lax), senna concentrate (X-Prep) Osmotics: polyethylene glycol (Colyte, Go-LYTELY, MiraLax), lactulose (Cephulac), glycerin Actions Stimulants: cause irritation, promoting peristalsis and evacuation of the bowel Osmotics: draw water into intestine from surrounding tissues Uses Relieve acute constipation Lactulose and polyethylene glycol are effective in relieving chronic constipation. Larger doses of polyethylene glycol are routinely used as bowel preparations before radiologic examination of abdominal organs. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Saline Laxatives Drugs Lubiprostone (Amitiza) Magnesium citrate (Citrate of Magnesia) Magnesium hydroxide (Dulcolax Liquid, Phillip’s Milk of Magnesia) Sodium phosphates (Fleet Phospho-Soda) Actions: draw water into the intestine from surrounding tissues, distending the bowel, causing peristalsis Uses: relieve acute constipation Usually act within 1 to 3 hours and up to 6 hours for sodium phosphates. Continuous use may alter electrolyte balance and cause dehydration. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Stool Softeners and Bulk-Forming Laxatives Action: draw water into bowel to soften stools; do not cause peristalsis Used routinely for prophylactic purposes Bulk-forming laxatives Action: cause water to be retained within the stool Drug of choice for those who use laxatives routinely; they absorb irritating substances and soften stools For specific drugs, see Table 35-1. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Lubricant Laxatives and Opioid Antagonist Action: lubricate intestinal wall, allowing for smooth passage of fecal contents Used as prophylactic for patients who should not strain during defecation Opioid antagonist Action: binds to opioid receptors in the GI tract, inhibiting constipation Used in treatment of opioid-induced constipation For specific drugs, see Table 35-1. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Drug Class: Antidiarrheal Agents Actions Locally acting agents: absorb excess water to cause a formed stool and adsorb irritants or bacteria causing diarrhea Systemic agents: act through autonomic nervous system to reduce peristalsis and motility of the GI tract, allowing the mucosal lining to absorb nutrients, water, and electrolytes, leaving a formed stool Uses Treat sudden-onset diarrhea, inflammatory bowel disease, post-GI surgery For specific drugs, see Table 35-2. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.

Drug Class: Antidiarrheal Agents (cont’d) Therapeutic outcomes Relief of incapacitation and discomfort of diarrhea Common adverse effects Abdominal distension, nausea, constipation Serious adverse effects Prolonged or worsened diarrhea Many OTC antidiarrheal medications are available. Mosby items and derived items © 2010, 2007, 2004 by Mosby, Inc., an affiliate of Elsevier Inc.