Chapter 58: Drugs Affecting Gastrointestinal Motility

While discussing the use of laxatives a student asks the nursing instructor what indicates normal bowel elimination. What would be the best response by the instructor?

"A soft, formed stool." Normal bowel elimination should produce a soft, formed stool without pain.

A client is scheduled for a colonoscopy in the morning. What laxative would the nurse expect to be prescribed the evening before the procedure?

Polyethylene glycol-electrolyte solution Saline or stimulant cathartics are acceptable as used for occasional bowel preparations for endoscopic or radiologic examinations.

A client is scheduled for a colonoscopy in the morning. The nurse will provide information concerning which laxative?

polyethylene glycol-electrolyte solution Polyethylene glycol-electrolyte solution is a nonabsorbable oral solution that induces diarrhea within 30 to 60 minutes and rapidly evacuates the bowel, usually within 4 hours for a colonoscopy. Psyllium is not strong enough for a colonoscopy preparation. Castor oil is not the most commonly prescribed preparation for a colonoscopy. Lactulose is used only when the serum ammonium level is elevated.

The nurse should know that lactulose achieves a therapeutic effect by which means?

pulling water into the intestinal lumen by osmotic pressure Lactulose is a disaccharide that is not absorbed from the GI tract. It exerts laxative effects by pulling water into the intestinal lumen. It does not change muscle tone, change the viscosity of bowel contents, or irritate the intestinal epithelium.

What is the correct rationale for why the nurse would administer a laxative at a separate time from the client's other medications?

Laxatives may reduce absorption of other drugs present in the GI tract. Laxatives may reduce absorption of other drugs present in the GI tract by combining with them chemically, or hastening their passage through the intestinal tract. Nausea, taste, and onset of action have no bearing on administration of laxatives.

A client is being sent home with orders for a laxative PRN. The nurse is conducting client teaching on the use of a laxative. What will the nurse inform the client is one of the most common adverse effects of a laxative?

Abdominal cramping Common adverse effects of laxatives are diarrhea, abdominal cramping, and nausea. CNS effects such as dizziness, headache, and weakness can occur. However, these adverse effects usually relate to the loss of fluid and electrolyte imbalance associated with laxative use and are not the most common adverse effects.

A nurse is caring for a patient with intestinal stenosis who has been prescribed psyllium. During the course of the treatment, the patient shows the signs of colon obstruction. What intervention should the nurse perform to avoid the occurrence of colon obstruction?

Administer the drug with adequate fluid intake. The nurse should administer the drug with adequate fluid intake to avoid obstruction of the esophagus, stomach, small intestine, and colon in a patient with intestinal stenosis. Mineral oil is given to the patient as a laxative on an empty stomach in the evening. The nurse should provide foods high in bulk or roughage to avoid constipation in a patient receiving laxatives. The nurse administers a laxative with an unpleasant or salty taste after chilling it to disguise its taste.

A nurse is caring for a client with pseudomembranous colitis. The health care provider has prescribed loperamide HCl to the client. How does the nurse know that the drug has been effective?

Diarrhea is resolved. Loperamide HCl (Lomotil) is an antidiarrheal medication. The nurse will know that the medication is effective if the diarrhea is resolved in the client. The nurse should monitor the client for an elevation in body temperature, severe abdominal pain, abdominal rigidity, or distention because these are the indicators of intestinal perforation. The nurse should monitor for rectal bleeding when laxatives are administered.

A 94-year-old client is to begin taking psyllium hydrophilic mucilloid daily. What instructions should the nurse include in the discharge teaching?

Drink at least 8 ounces of fluid with the medication. Psyllium needs to be taken with at least 8 oz of water or other liquid. The nurse would not tell the patient to mix the medication with food, to add all medications to the psyllium, or to discontinue the drug.

What recommendations should be included in client teaching as a means of avoiding constipation? (Select all that apply.)

Drink plenty of fluids. Be active and exercise daily. Eat foods high in bulk or roughage.

When describing the drugs used to treat traveler's diarrhea, which would the nurse identify as the most common cause?

E. coli The most common cause of traveler's diarrhea is E. coli.

In pharmacology class the students are learning about the mechanism of action of different laxatives. What would the students learn about the mechanism of action of psyllium hydrophilic mucilloid?

Increasing mass and water content of stool When water is added, the laxative substance swells and becomes gel-like. The added bulk or size of the fecal mass stimulates peristalsis and defecation. The other options are not the mechanism of action of psyllium.

What is the reason for administering a bulk-forming laxative like polycarbophil to a client experiencing liquid stools?

Polycarbophil absorbs large amounts of water and decreases fluidity of stools. Polycarbophil is an adsorbent drug that works by absorbing large amounts of water and produces stools of gelatin-like consistency. Polycarbophil will not diminish the absorption of intestinal fiber and water. Polycarbophil will cause abdominal discomfort and bloating. Polycarbophil has no effect on bacterial flora in the intestines.

A client is scheduled for a colonoscopy. The nurse knows that the preferred drug for bowel cleansing before this procedure is:

Polyethylene glycol-electrolyte solution (NuLYTELY) Polyethylene glycol-electrolyte solution taken orally will rapidly provoke extensive diarrhea with complete emptying of the lower intestine. Polyethylene glycol solution, bisacodyl, and psyllium work much more slowly and are useful in managing constipation.

Which is an important assessment for the nurse to make before administering a laxative?

Question the client regarding the type and intensity of symptoms to provide a baseline evaluation.

A client is admitted to the hospital for pneumonia. Since admission, the client has not had a bowel movement. The physician prescribes magnesium hydroxide. What should be an outcome of this therapy?

The client will have a bowel movement after taking the drug. The desired outcome for magnesium hydroxide therapy would be for the client to have a bowel movement after taking the drug. Within 2 to 3 hours of using simethicone, the client will experience a decrease in abdominal pain and distention. Diarrhea will be controlled through the use of diphenoxylate HCl with atropine sulfate. The client will not sustain injury using diphenoxylate HCl with atropine sulfate.

The nurse is preparing to administer a stimulant cathartic to the client. The nurse should inform the client of the possible adverse effect of:

diarrhea. Diarrhea may result due to the action of strong, stimulant cathartics. A stimulant cathartic would not cause nausea, vomiting, or rectal bleeding.

To maximize the therapeutic effect of diphenoxylate HCl with atropine sulfate, the nurse will instruct the client to take the medication:

four times a day. To maximize the therapeutic effect, diphenoxylate HCl with atropine sulfate is usually administered four times daily, which serves to help maintain a therapeutic drug level.

Which is a likely cause of diarrhea experienced by an older adult?

laxative abuse Laxative abuse is associated with diarrhea. This phenomenon is particularly common among older adults. Antihypertensive agents and anemia are not associated with diarrhea. Fluid volume deficit is a result, not cause, of diarrhea.

A hospitalized client's request for a magnesium citrate "bisacodyl pill" every night to "keep regular" should alert the nurse to what potential health risk for the client?

laxative abuse Stimulant laxatives such as bisacodyl are generally useful and safe for short-term treatment of constipation, cleansing the bowel prior to endoscopic examinations, and treating fecal impaction. However, they are not safe for frequent or prolonged usage but are often used or overused in older adults.