GI drugs Flashcards
What are the antidiarrheals?
Bismuth-subsalicylate
Diphenoxylate HCL
Loperamide hydroxychloride
What are the different categories of laxatives?
Bulk-forming laxatives
Hyperosmotic cathartics
stool softeners
lubricants
saline laxatives
What are the bulk forming laxatives?
Psyllium
Bisacodyl
What are the hyperosmotic cathartics?
polyethylene glycol
What are the stool softeners?
docusate sodium
docusate sodium and senna
what are the lubricants?
mineral oil
what are the saline laxatives?
Magnesium hydroxide
Magnesium citrate (Best for Bowel Prep!)
Sodium phosphate
What are the different antiemetics groups?
antihistamines
serotonin receptor antagonist
anticholinergic
phenothiazine
What are the antihistamine antiemetics?
hydroxyzine hydrochloride
mecllizine hydrochloride
dimenhydrinate
What are the serotonin receptor antagonist antiemetics?
ondansetron hydrochloride
metoclopramide
What are the anticholinergic antiemetics?
scoplamine
What are the phenothiazine antiemetics?
prochlorperazine
promethazine hydrochloride
- Slow and/or inhibit GI motility by acting on nerve endings of the intestinal wall, thereby reducing the volume of stools, increasing viscosity and decreasing fluid and electrolyte loss.
- Used for symptomatic relief of acute nonspecific ______ and _______of inflammatory disease.
action and use for antidiarrheals
diarrhea,
- Shake suspensions well; chew tablets thoroughly
- Stool may appear gray-black (may mask GI bleeding)
- Do not give concurrently with other medications
- Seek medical care if diarrhea persists for more than two days in an adult
- Do not use to treat _____ in children; seek medical attention
- Do not give to clients with C. difficile
administration considerations for antidiarrheals
diarrhea
- Presence of bloody diarrhea, diarrhea associate with pathogens such as E. coli, salmonella or psuedomembranous colitis, or other bacterial toxins
- Avoid use if obstructive bowel disease is suspected
- Avoid bismuth subsalicylate if allergic to aspirin
contraindications for antidiarrheals
- Allergies to aspirin or other salicylates since bismuth subsalicylate contains salicylate
- Avoid aspirin use as concomitant use with bismuth subsalicylate , which may cause aspirin toxicity
- Bismuth may also decrease tetracycline absorption in the GI tract
- Diphenoxylate/atropine sulfate may increase the sedative effects of barbiturates, narcotics and alcohol.
- Concomitant use with MAO inhibitors may increase the risk of hypertensive crisis
significant drug interactions with antidiarrheals
are there significant food interactions with antidiarrheals?
no
______ may increase serum amylase levels
Diphenoxylate
- Nausea and vomiting
- Dry mouth, dizziness, drowsiness and constipation
- Temporary darkening of stools and tongue may occur with bismuth salicylate
side effects of antidiarrheals
- Clinical signs and symptoms of overdose include drowsiness, decreased blood pressure (BP), seizures, apnea, blurred vision, dry mouth and psychosis
- Risk of aspirin toxicity with concurrent use of aspirin and bismuth subsalicylate
- Other adverse effects include central nervous system (CNS) depression, respiratory depression, hypotonic reflexes, angioedema, anaphylaxis and paralytic ileus
adverse effects/toxicity for antidiarrheals
- Note allergies
- Document onset, duration, and frequency of symptoms
- Document previous therapies used
- Note current medications
- Identify any causative factors; perform stool analysis if necessary and ordered
- Assess for evidence of dehydration or electrolyte imbalance
- Monitor vital signs and I&O
- Note presence of comorbid conditions
- Check abdomen for tenderness, distention, bowel sounds or masses
- Administer bismuth and tetracycline one hour apart
nursing considerations for antidiarrheals
- Withhold solid food and 24 hours with acute diarrhea
- Foods that aggravate diarrhea include milk products, fruit and fruit juices, coffee, tea with caffeine and chocolate
- Drink fluids to avoid dehydration and alleviate dry mouth
- Follow the BRAT diet-bananas, rice, applesauce, tea/toast-to avoid dehydration if recommended by health care provider (controversial)
- Do not exceed prescribed dose
- Consult health care provider if diarrhea persists over two days
- Use caution in activities requiring alertness if dizziness or drowsiness is present (possible side effects)
- Report fever, nausea, and vomiting, abdominal pain or distention
- Avoid OTC antacids, dairy products, and other foods that aggravate diarrhea
- Use good personal hygiene to avoid skin irritation or breakdown because of diarrhea
- Avoid alcohol ingestion while taking medication
- Notify health care provider if pregnant or breastfeeding
education with antidiarrheals
a. Include nonabsorbable polysaccharide and cellulose derivatives
b. __________ absorb water to increase bulk in fecal mass
c. Peristalsis is stimulated by the increased fecal mass, which decreases bowel transit time
d. They generally produce a laxative effect within 12-14 hours but may require 2-3 days for full effect
e. Are frequently are used to prevent straining with defecation in clients who are post-myocardial infarction or have other conditions in which straining at stool could be harmful
Bulk-forming laxatives action and use
a. Since these agents rely on water to increase their bulk, it is essential that adequate fluids be given for bowel absorption
b. These agents may also cause intestinal and esophageal obstruction when insufficient liquid is administered with the dose
c. Each dose should be given with a full glass of liquid (240 mL)
d. Use sugar-free preparations in clients with phenylketonuria
bulk forming laxatives administration considerations
a. Not recommended for clients with intestinal stenosis, ulceration, or adhesions
b. Use cautiously in clients swallowing difficulties to ensure aspiration does not occur
c. Do not use if fecal impaction is present
contraindications for bulk forming laxatives
: decreased GI absorption may occur with digitalis, anticoagulants, nitrofurantoin and salicylates
significant drug interactions with bulk forming laxatives
a. Dietary management of constipation can be aided by encouraging the intake of fluid and fiber
b. Fiber increases stool bulk and water retention in the bowel
c. A dietary bulk forming nutrient such as bran is an appropriate adjunctive therapy for constipation
d. Bran is only partially fermented by bacteria, resulting in increased stool bulk, accelerated transit time, and promotion of normal defecation
e. Rapid increases in dietary roughage may cause abdominal bloating and flatulence
f. Adequate fluid intake is also necessary in order to prevent fecal impactions
g. Generally 240 to 360 mL of fluid with each tablespoon of bran is sufficient
h. Avoid foods that reduce stool, such as bananas, rice, breads, and cheeses
significant food interactions with bulk forming laxatives
Are there significant laboratory studies reported with bulk forming laxatives?
no
a. abdominal discomfort and/or bloating flatulence
b. Nausea, vomiting, diarrhea
side effects of bulk forming laxatives
a. Rare reports of allergic reactions karaya such as urticaria, rhinitis, dermatitis and bronchospasm
b. Esophageal obstruction, swelling, or blockage may occur when insufficient fluid is used in mixing a bulk-forming laxative
adverse effects/toxicity with bulk forming laxatives
a. Assess degree of abdominal distention, bowel sounds, and bowel elimination patterns
b. Assess swallowing ability, adequately mix agents in liquid and encourage additional fluid intake
c. Monitor for aspiration
d. If administered via feeding tube, it must be a large bore tube, and medication must be adequately dissolved in liquid and given rapidly with adequate flushing
e. Add at least 8 oz (240 mL) of water or juice to drug
f. Separate psyllium administration from digoxin, salicylates and anticoagulants by 2 hours
g. Use sugar free preparations in diabetic clients
nursing considerations with bulk forming laxatives
a. These agents require adequate hydration to be effective
b. Additional fluids and exercise are helpful in aiding bowel elimination
c. Mix powder preparation with at least 8 oz fluid and drink immediately and follow with another 8 oz of fluid
d. Bulk-forming laxatives may decrease appetite if taken before meals
e. Take bulk-forming laxatives 2 hours after meals and any oral medications
f. Use sodium and sugar-free preparations if they are appropriate to individual diet restrictions
g. Full effect of medication not occur for 2-3 days
client education for bulk forming laxatives
a. called _____ because they ______ peristalsis via mucosal irritation or intramural nerve plexus activity, which results in increased motility
b. _____ are agents with purgative actions
c. It is proposed that _________ modify the permeability of the colonic mucosal cells, which result in intraluminal fluid and electrolyte secretion
d. Defecation occurs between 6-12 hours after oral administration of these agents
e. Rectal administration of bisacodyl and senna produces catharsis within 15 minutes to 2 hours
stimulants
stimulate
Cathartics
stimulant laxatives
a. Bedtime administration of dose promotes a morning bowel movement
b. Swallow tablet whole; do not crush
c. Do not take within 1 hour of antacids or milk
d. Mix castor oil with 8 oz of water or juice; this drug is usually limited to use for rapid bowel evacuation, such as before radiological procedures
administration considerations for stimulant cathartics
a. Contraindicated with abdominal pain, nausea, and vomiting, symptoms of appendicitis, rectal bleeding, gastroenteritis, intestinal obstruction, fecal impaction
b. Castor oil may induce premature labor
c. Use senna cautiously nursing mothers as senna is excreted in breast milk
contraindications for stimulant cathartics
Significant Drug interactions
Significant Food interactions
Significant laboratory studies: NONE REPORTED
stimulant cathartics
a. Nausea, vomiting, abdominal cramps, diarrhea, laxative dependence
b. Muscle weakness, fluid and electrolyte imbalance
c. Rectal burning or irritation with suppository use
side effects for stimulant cathartics
a. Hypolkalemia, hypocalcemia
b. Metabolic acidosis or alkalosis
adverse effects for stimulant cathartics
a. Evaluate for nausea and vomiting, abdominal pain or diarrhea
b. Evaluate for medication effectiveness
c. Monitor for fluid and electrolyte imbalances
d. Administer medication 1 hour before or after ingestion of milk or an antacid
e. Encourage increased fluids and diet alterations to include increased amounts of high-fiber foods
f. Evaluate for laxative dependence and offer counseling
nursing considerations for stimulant cathartics
a. Discourage client from chronic use of laxatives; use beyond 1 week should be avoided
b. These agents may produce a cathartic colon if used for several years; the colon develops abnormal motor function, and on x-ray resembles ulcerative colitis; usually discontinuation of laxative use restores normal bowel function
c. Increase fluid intake and diet high in fiber
d. Report signs and symptoms of side effects immediately
client education for stimulant cathartics
a. They increase osmotic pressure within the intestinal lumen, which results in luminal retention of water, softening the stool
b. Lactulose is an unabsorbed disaccharide metabolized by colonic bacteria primarily to lactic acid, formic and acetic acids
c. It has been proposed that these organic acids may contribute to the osmotic effect
d. Used for treatment of occasional constipation
e. Used to reduce ammonia levels (Lactulose)
action and use for hyperosmotic cathartics
a. Glycerin is available only for rectal administration (suppository or enema) for treatment of acute constipation; its laxative effect occurs within 15-30 minutes
b. Lactulose may require 24 to 48 hours for effect; it is also more costly and should be reserved for acute constipation
c. Dissolve 17 grams Miralax in 8 oz water and use once daily for up to 2 weeks; it may take 2 to 4 days for results to occur
administration considerations for hyperosmotic cathartics
Contraindicated in bowel obstruction
b. Use lactulose cautiously in clients with diabetes mellitus
contraindications for hyperosmotic cathartics
- Significant drug interactions: antibiotics may decrease laxative effect by elimination of bacteria needed to digest active form
- Significant food interactions: none reported
- Significant laboratory studies: serum electrolyte levels
interactions and lab studies for hyperosmotic
Glycerin: rectal irritation and burning, hyperemia of the rectal mucosa
b. Lactulose and Miralax: flatulence, abdominal cramps and bloating, diarrhea
9. Adverse effects/toxicity: fluid and electrolyte imbalances
side effects and adverse effects/toxicity for hyperosmotics
a. Miralax should always be dissolved in 8 oz of water
b. Dilute lactulose in water or juice to decrease sweet taste
c. Monitor frequency and consistency of stools
d. Monitor for electrolyte imbalances, especially in older adults
nursing considerations for hyperosmotics
a. Miralax should be dissolved in 8 oz of water
b. Medication may take 2 to 4 days for effect
c. Contact prescriber if unusual bloating, cramping, or diarrhea occurs
d. Prolonged use may result in electrolyte imbalance and laxative dependence
e. Take medication with juice to improve taste
client education for hyperosmotics
a. Used on a scheduled basis for clients who are likely to become constipated, such as with hospitalization, bed rest, postsurgical status, and for those receiving opioid analgesic medications
b. ______ are often referred to as emollient laxatives
c. They are anionic surfactants that lower the fecal surface tension in vitro by allowing water and lipid penetration
d. Softening of the feces generally occurs after 1 to 3 days
e. Some preparations combine a _________such as docusate sodium with a stimulant, such as casanthranol to make a single combination product (e.g. Pericolace)
f. Used for constipation associated with dry, hard stools and to decrease strain of defecation
Stool softeners action and use
a. Do NOT give with mineral oil
b. Offer fluids after each PO dose
administration considerations for stool softeners or emollient laxatives
a. Contraindicated with any hypersensitivity to the drug
b. Contraindicated with intestinal obstruction undiagnosed abdominal pain, vomiting or other signs of appendicitis, fecal impaction or acute abdomen
c. Docusate sodium should not be used by clients with congestive heart failure (CHF) because of sodium content
contraindications for stool softeners or emollient laxatives
- Significant drug interactions: may increase absorption of mineral oil
- Significant food interactions: none reported
- Significant laboratory studies: none reported
interactions associated with stool softeners or emollient laxatives
Side effects
a. Mild abdominal cramping, diarrhea
b. Dependence with long-term use or excessive use
c. Bitter taste
Adverse effects/toxicity (all rare)
a. Throat irritation has occurred with docusate sodium solution
b. Docusate potassium has been associated with hyperkalemia when used in clients who have renal insufficiency or renal failure
side and adverse effects associated with stool softeners or emollient laxatives
a. Monitor frequency and consistency of stools
b. Monitor for electrolyte imbalances especially in older adults
nursing considerations with stool softeners
a. Take medication with milk or juice to decrease bitter taste
b. Increase fluid intake if not contraindicated by another condition such as CHF or renal failure
c. It may require 1 to 3 days to soften fecal matter
d. Consult with dietician regarding dietary changes to increase fiber foods
e. Avoid prolonged use
client education for stool softeners
a. Provide lubrication of feces and hinder water reabsorption into the colon
b. Used to treat constipation and prepare client for bowel studies or surgery
action and use for lubricants
Mineral oil is indigestible, and its absorption is limited considerably in the non-emulsified formulation
Onset of action when taken orally is 6 to 8 hours
administration and considerations for stool lubricants