GI Abrams Ch 39,40

What is constipation?

Infrequent and painful expulsion of hard, dry stools.

What is defecation?

Bowel elimination that is normally stimulated by movements and reflexes in the gastrointestinal tract.

What is fecal impaction?

A mass of hard, dry stool in the rectum caused by chronic constipation.

What does flatulence refer to?

The expulsion of gas through the rectum.

What are laxatives?

Drugs used to promote bowel elimination, implying mild effects with elimination of soft, formed stool.

What are cathartics?

Drugs that imply strong effects, leading to the elimination of liquid or semiliquid stool.

Is constipation a disease?

No, constipation is a symptom, not a disease.

What are some risk factors for constipation?

Age, diet and lifestyle (especially decreased physical activity), certain drugs, and disease processes.

What is the traditional medical definition of functional constipation in adults?

Three or fewer bowel movements per week.

What are the Rome III criteria for functional constipation in adults?

Two or more of six symptoms during at least one fourth of bowel movements, including straining and hard stools.

What are the criteria for constipation in children under 4 years old?

Fewer than two stools per week, at least one episode of incontinence, stool retention, painful bowel movements, or large mass of stool in the rectum.

What lifestyle changes can help alleviate constipation?

Increased fiber intake, fluid supplementation, and behavioral therapy.

What types of foods can improve bowel transit time?

Increased fruits, vegetables, and whole grains.

What is the role of biofeedback therapy in treating constipation?

It has been successful in improving symptoms of constipation.

What are bulk-forming laxatives?

Soluble fibers that swell and become gel-like when water is added.

What are some examples of bulk-forming laxatives?

Psyllium preparations, methylcellulose, and polycarbophil.

What is the purpose of measuring bowel transit time?

To find the cause of constipation or identify specific parts of the intestine slowing down movement.

What are stimulant cathartics?

Drugs that induce bowel movements by stimulating the intestinal lining.

What are saline cathartics?

Drugs that draw water into the intestines to promote bowel movements.

What is the significance of patient motivation in biofeedback therapy?

It improves the chance of successfully resolving constipation.

What is the clinical application for assessing constipation in patients?

Nurses assess bowel patterns and risk factors related to constipation.

What are some indications for using laxatives and cathartics?

To relieve constipation, prevent straining, and prepare for bowel surgery or diagnostic procedures.

What is the effect of dietary juices like prune or pear juice on constipation in children?

They can help alleviate constipation due to their sorbitol content.

What is the role of significant others in treating childhood constipation?

They play an important role in supporting behavioral interventions.

What is the impact of certain drugs on intestinal motility?

Drugs like opioid analgesics can decrease intestinal motility, leading to constipation.

What is the purpose of stool softeners?

To ease the passage of stool by increasing moisture content.

What are some miscellaneous agents used for constipation treatment?

Linaclotide, lactulose, and prucalopride.

What happens to substances when water is added?

They swell and become gel-like.

Why are bulk-forming laxatives considered the most physiologic?

Their effect is similar to increased intake of dietary fiber.

What is the prototype bulk-forming laxative?

Psyllium (Metamucil).

How long does psyllium usually take to act?

12 to 24 hours, but may take 2 to 3 days for full effects.

How does psyllium work in the body?

It absorbs excess water and stimulates normal bowel elimination.

What are the uses of psyllium?

Treatment of occasional constipation, bowel irregularity, and may help lower cholesterol.

What should be noted about psyllium's absorption?

It is essentially unabsorbed by the body.

What are the contraindications for using psyllium?

Undiagnosed abdominal pain, known allergy, intestinal obstruction, and fecal impaction.

What adverse effects can psyllium cause?

Severe flatulence, bloating, abdominal cramping, and potential bowel obstruction.

What is the recommended fluid intake when taking psyllium?

At least 8 oz of water or another liquid.

What is the preferred laxative for patients with coronary artery disease?

Stool softeners like docusate sodium.

What laxatives are acceptable for children for bowel cleansing?

Saline or stimulant cathartics such as magnesium citrate or bisacodyl.

What laxative is preferred for long-term use in debilitated patients?

Bulk-forming laxatives like Metamucil.

What should be avoided when using bulk-forming laxatives?

Giving them to patients with difficulty swallowing or GI tract strictures.

What is the first-choice laxative for adults with irritable bowel syndrome with constipation?

Polyethylene glycol (PEG).

What is the role of lactulose in hepatic encephalopathy?

It acidifies stool and traps ammonia for elimination.

What is the risk associated with taking psyllium without sufficient fluids?

Potential obstruction in the GI tract.

What should be monitored when administering psyllium?

Potential interactions with medications and nutrient absorption.

What is the dosage range for adults taking psyllium?

2.5-30 g daily in divided doses.

What is the maximum daily dose of psyllium for children aged 6-11?

1.25-15 g daily in divided doses.

What is a common side effect of stimulant laxatives?

Abdominal pain.

What is the recommended administration method for psyllium capsules?

Take one at a time with ample fluids.

What is the effect of psyllium on cholesterol levels?

It may help lower cholesterol when combined with a low-cholesterol diet.

What is the recommended action for fecal impaction in adults?

Use a rectal suppository or enema.

What laxative is often used for initial disimpaction in children?

Polyethylene glycol with or without electrolytes.

What should be done after relieving fecal impaction?

Prevent recurrence with dietary measures or bulk-forming agents.

What is the significance of the bulk-forming action of psyllium?

It adds bulk to fecal mass, stimulating peristalsis and defecation.

What is the importance of monitoring for esophageal stricture when administering psyllium?

Patients with esophageal narrowing should not take psyllium due to obstruction risk.

What is the effect of psyllium on bowel elimination?

It stimulates normal bowel elimination by adding bulk and size to fecal mass.

How should capsules be taken?

One at a time with ample fluids.

What is the time frame for assessing relief from constipation after taking laxatives?

Within 12 to 72 hours.

What adverse effects should a nurse assess for when administering laxatives?

Choking, severe stomach pain, nausea, vomiting, rectal bleeding, or constipation lasting longer than 7 days.

What should patients be taught about taking laxatives?

To take the medication as directed with a full glass of liquid and maintain adequate fluid intake.

What is a safety concern regarding psyllium products?

They may contain sugar, sodium, potassium, or artificial sweeteners, which can be concerning for patients with certain health conditions.

What is the only lubricant laxative used clinically?

Mineral oil.

What is the mechanism of action of mineral oil?

It lubricates the fecal mass and slows colonic absorption of water, but its exact mechanism is unknown.

What are the potential adverse effects of oral mineral oil?

Decreased absorption of fat-soluble vitamins and lipid pneumonia if aspirated.

What is the prototype stimulant cathartic?

Bisacodyl (Dulcolax).

How does bisacodyl work?

It irritates the GI mucosa and pulls water into the bowel lumen, leading to watery stool elimination.

What are the common uses of bisacodyl?

For relief of constipation and bowel preparation before medical examinations and surgery.

What age group should stimulant laxatives generally be avoided in?

Children younger than 6 years of age.

What are common adverse effects of bisacodyl?

Abdominal pain, cramping, nausea, diarrhea, and weakness.

What are contraindications for bisacodyl?

Known allergy to the drug, undiagnosed abdominal pain, intestinal obstruction, or fecal impaction.

How should bisacodyl be administered for optimal effect?

On an empty stomach or at bedtime, and the drug should be swallowed whole.

What should be avoided when taking bisacodyl?

Taking it within an hour after ingesting milk, as it can reduce the drug's effectiveness.

What is the typical onset time for oral bisacodyl?

6 to 12 hours.

What is the typical onset time for rectal bisacodyl?

15 minutes to 1 hour.

What should patients be cautioned against regarding bisacodyl use?

Frequent use or use for longer than 1 week due to potential electrolyte and acid-base imbalances.

What is the half-life of bisacodyl?

16 hours.

How is bisacodyl primarily excreted from the body?

In the feces, with any absorbed portion excreted in the urine.

What patient-related variable should be considered when using bisacodyl?

Reproductive status, as its use should be limited during pregnancy.

What is the risk associated with some dosage forms of bisacodyl in neonates?

Potentially fatal toxicity known as 'gasping syndrome' due to a benzyl alcohol derivative.

What is the role of adequate fluid intake in laxative use?

It helps improve bowel regularity.

What is the route and dosage for Bisacodyl in adults?

PO 10-15 mg; Rectal suppository 10 mg

What is the recommended dosage of Castor oil for children aged 2-11?

PO 5-15 mL as a single dose

How is Glycerin administered for adults?

Rectal suppository, 1 adult suppository once daily as needed or directed

What is the dosage range for Senna preparations for adults?

Granules: PO 1 level tsp once or twice daily; Syrup: PO 10-15 mL once or twice daily; Tablets: PO 2 tablets once or twice daily

What is the maximum dosage of Magnesium citrate solution for adults?

PO 195-300 mL given once or in divided doses

What is the dosage of Milk of Magnesia for children aged 2-5?

PO 400-1200 mg once daily at bedtime or in divided doses

What is the dosage of Polyethylene glycol (PEG) solution for bowel preparation?

PO 17 g in 4-8 oz water or beverage or as ordered

What is the primary use of Saline cathartics?

To increase osmotic pressure in the intestinal lumen and cause water retention for rapid bowel evacuation

What are the adverse effects of Saline cathartics?

Fluid and electrolyte imbalances, especially in patients with impaired kidney function or congestive heart failure

What is the mechanism of action of Guanylate cyclase-C agonists?

They manage symptoms of chronic idiopathic constipation and IBS-C by promoting more frequent and complete bowel movements

What is the prototype drug in the Guanylate cyclase-C agonists class?

Linaclotide (Linzess)

What should patients be instructed regarding Bisacodyl tablets?

Swallow the tablets without chewing and not take them within an hour after ingesting milk or gastric antacids

What are the contraindications for Polyethylene glycol-electrolyte solution (PEG-ES)?

GI obstruction, gastric retention, colitis, or bowel perforation

What is the effect of Magnesium hydroxide (Milk of Magnesia)?

Increased osmotic pressure in the intestinal lumen

What is the effect of Glycerin as a laxative?

It exerts hyperosmotic effects in the colon, acting within 30 minutes

What is the recommended dosage of PEG-ES for bowel cleansing before GI examination?

PO 240 mL every 10 min until 4 L is consumed or until rectal fluid is clear

What should be monitored when administering cathartics?

Bowel elimination patterns, presence of diarrhea, abdominal pain, cramping, nausea, or weakness

What is the recommended dosage of PEG solution for maintenance?

PO 0.2-0.8 g/kg/d daily in 60 mL of noncarbonated beverage

What is the effect of oral magnesium preparations?

Effects occur within ½ to 6 hours

What is the maximum dosage of Magnesium hydroxide for adults?

8 tablets/d once daily at bedtime or in divided doses