GI Flashcards
3 primary benefits of Lorazepam?
- Sedation
- Suppression of anticipatory emesis.
- Production of anterograde amnesia.
What is the therapeutic effect of Group 3 laxatives?
acts within 1-3 days to produce a soft, formed stool; uses include treating chronic constipation and preventing straining at stool
Which osmotic laxative is used for chronic constipation?
polyethylene glycol (Miralax); group 3
Phenothiazines end in what?
-zine
MOA of Misoprostol?
Suppress secretion of gastric acid, promotes bicarbonate release, and promotes improved gastric blood flow
Side effect of Senna?
May cause yellowish-brown or pink colored urine.
Aluminum hydroxide can reduce the effectiveness of which drugs?
tetracyclines, warfarin, digoxin; timing administration is important
What is the therapeutic effect of Group 2 laxatives?
acts within 6-12 hours and produces a semifluid stool.
Therapeutic use of Omeprazole?
PUD and GERD
Adverse effects of aluminum hydroxide?
constipation and hypophosphatemia
Adverse effects of Lomotil?
Tachycardia, dizziness, headache, flushing, nausea and vomiting, dry skin and mucous membranes, and urinary retention.
Prototype for PPIs
Omeprazole
What is the liquid formula of magnesium hydroxide called?
Milk of Magnesium (MOM)
Antihistamines used for N/V associated with motion sickness?
Dimenhydrinate, meclizine, cyclizine
PPIs end with what?
-prazole
What is Loperamide (Imodium) used for?
diarrhea and to reduce the volume of discharge from ileostomies.
What are drugs used for N/V associated w/ motion sickness?
Scopolamine and antihistamines
MOA of Sucralfate?
coats the stomach to protect against acid and pepsin
Therapeutic use of Bisacodyl?
opioid induced constipation and constipation from slow intestinal transit; PCA pump.
What are the 2 groups of laxative salts?
sodium phosphate and magnesium salts (Mag citrate, MOM, Mag sulfate)
Adverse effects of Omeprazole?
Fractures, pneumonia, acid rebound, intestinal infection withClostridium difficile, and low Mg levels
MOA of Metoclopramide?
blocks dopamine receptors in CTZ.
Bulk forming group 3 laxatives prototype?
Psyllium (Metamucil)
Famotidine uses?
Gastric and duodenal ulcers
What are sx of hypomagnesemia?
tremors, muscle cramps, seizures, and dysrhythmias
Side effects of Meclizine?
Sedation, dry mouth, blurred vision, urinary retention, constipation
MOA of opioids as antidiarrheal agents?
activate mu receptors of the GI tract causing:
- reduce intestinal motility
- Slow intestinal transit
- Allow more fluid to be absorbed.
- Decrease secretion of fluid into small intestine and increase absorption of fluid and salt.
Adverse effects of Misoprostol?
Diarrhea and abdominal cramping
2 uncommon effects that occur with really high doses of Lomotil?
hypotension and respiratory depression
Therapeutic use of Diphenoxylate w/ atropine (Lomotil)?
treat moderate to severe diarrhea
Therapeutic uses of Dronabinol?
- Suppresses CINV
2. Appetite stimulant
Therapeutic uses of Promethazine?
N/V associated with surgery, cancer, chemotherapy, and toxins.
Sucralfate (Carafate) belongs to which class?
Mucosal protectant
Adverse effects of Metoclopramide?
Sedation, diarrhea, TD.
What is the prototype for a group 3 surfactant laxative?
Docusate sodium (Colace)
What are the different types of osmotic laxatives?
laxative salts, polyethylene glycol, and lactulose.
Therapeutic uses of Ondansetron?
N/V associated w/ chemoradiation and anesthesia
Why is Atropine combined with Diphenoxylate?
To discourage diphenoxylate abuse
Which antacid is the drug of choice and why?
Magnesium hydroxide; rapid-acting, has high Acid Neutralizing Capacity, and produces long-lasting effects
Which laxatives are used for fecal impaction?
mineral oil and glycerin suppository
Why is milk of magnesium often used as a laxative?
Because one of the adverse effects is diarrhea
MOA of cyclizine/meclizine/dimenhydrinate? *antihistamine for motion sickness
block Ach and histamine receptors
Consideration for PEG plus ELS?
- Isotonic with body fluids.
2. Requires ingestion of large volume of bad-tasting liquid.
Adverse effects of calcium carbonate?
acid rebound; constipation; milk-alkali syndrome, a condition characterized by hypercalcemia & metabolic alkalosis, soft tissue calcification, impaired renal function, burping and farting
Most commonly used opioids as antidiarrheal agents?
Diphenoxylate (Lomotil) and loperamide (Imodium)
What is the therapeutic effect of Group 1 laxatives?
Act within 2-6 hours and give stool a watery consistency; useful for preparing bowel for diagnostic procedures or surgery
Adverse interactions with Omeprazole
Antivirals, Clopidogrel (plavix), and some antifungals
MOA of Lomotil?
slows peristalsis by acting on the smooth muscles in the intestine. Atropine is an anti-cholinergic.
Why does magnesium hydroxide need to be avoided in patients with undiagnosed abdominal pain?
stimulation of the bowel can be hazardous for patients with intestinal obstruction or appendicitis
Therapeutic use of castor oil?
Bowel prep because it is rapid acting
Therapeutic use of Docusate sodium (colace) ?
prevention of constipation
When is a high dose of laxative salts used?
emergent expulsion (2 – 6 hours), to rid the body of ingested poison, dead parasites following anthelmintic treatment, or prep for surgery
Contraindications of Misoprostol?
Pregnancy-Category X because prostaglandins can stimulate contractions.
Adverse effects of Chlorpromazine?
*blurred vision, urinary retention, dry mouth, photosensitivity, drowsiness, and confusion (strong anti-cholinergic signs). * hypotension and sedation. TD with long term use.
What is the most effective antidiarrheal agents?
opioids; non specific
Caution use of Prochlorperazine with?
The elderly and people with liver impairment
Why does aluminum hydroxide need to be avoided in heart failure patients?
has a lot of salt
Prototypes for stimulant laxative?
- Bisacodyl (Dulcolax)
- Senna (Senokot, Ex-lax).
- Castor oil
Which other antacid is is rapid-acting, has high ANC (acid neutralizing capacity), and produces effects of long duration?
Calcium carbonate
What are 3 kinds of bowel prep cleansers?
(1) sodium phosphate
(2) a combination of sodium picosulfate, magnesium oxide, and citric acid
(3) PEG plus electrolytes (ELS)
Which osmotic laxative is used to lower ammonia levels r/t liver issues?
Lactulose
Why should Omeprazole be taken for short-term?
D/t serious adverse effects
Caution use of Ondansetron in people with?
electrolyte abnormalities, heart failure, bradysyrhythmias, and other drugs that increase risk of QT prolongation.
MOA of Prochlorperazine?
block dopamine receptors in the CTZ
Contraindication for Promethazine?
not for children <2 d/t respiratory depression
Therapeutic uses of Metoclopramide (Reglan)?
o PO: diabetic gastroparesis and suppression of gastroesophageal reflux.
o IV: Postoperative nausea/vomiting, anticancer drug, opioids, toxins, radiation therapy.
o Off label: hiccups and nausea and vomiting of early pregnancy.
3 types of antacids?
magnesium hydroxide, aluminum hydroxide, and calcium carbonate
Adverse effects of scopolamine?
anti-cholinergic effects like dry mouth, blurry vision, drowsiness.
Adverse effects of Ondansetron?
*Headache, *diarrhea, *dizziness, prolonged QT interval, risk of torsades de pointes.
Adverse effects of Psyllium?
Esophageal obstruction
Contraindications for Metoclopramide?
patients with GI obstruction, perforation, or hemorrhage.
Why is milk of magnesium often administered in combination with aluminum hydroxide?
Because aluminum hydroxide has an adverse effect of constipation so they balance each other out.
Adverse effects of Polyethylene glycol (Miralax)?
bloating, cramping, and flatulence.
What are the antiandrogenic adverse effects of Cimetidine?
gynecomastia, reduced libido, and impotence
Considerations for sodium phosphate?
- Hypertonic with body fluids.
- Can cause dehydration and electrolyte disturbance
- Possibility of renal damage
Prototype for antiemetic in the THC family?
Dronabinol (Marinol)
What are the 4 classification of laxatives?
- Bulk forming
- Surfactant
- Stimulant
- Osmotic
H2 blockers end in what?
-tidine
Considerations for glycerin suppository?
- May also stimulate rectal contraction
2. Expect to see BM 30 minutes after suppository insertion.
What are the 2 major groups of antidiarrheals?
Specific: goal is to treat the infection causing the diarrhea.
Non specific: goal is to slow down the diarrhea (Lomotil, Imodium)
When is a low dose laxative salt used?
To stimulate a stool in 6-12 hours.
What anxiolytic can also be used prophylaxis for chemotherapy induced nausea/vomiting?
Lorazepam (Ativan)
Adverse effects of Sucralfate?
constipation
Misoprostol (Cytotec) belongs to which class?
Analog of prostaglandin E1
Therapeutic uses of Psyllium?
- Temporary tx of constipation in diverticulosis and IBS.
- Symptomatic relief of diarrhea in colostomy and ileostomy patients.
Two effects of Bisacodyl on bowel?
Stimulate intestinal motility & Increase amounts of water and electrolytes in intestinal lumen
MOA of Famotidine?
suppress secretion of gastric acid by blocking histamine2receptors on parietal cells of the stomach
Adverse effects of mineral oil?
Lipid pneumonia, anal leakage, and deposition of mineral oil in the liver.
What are the CNS adverse effects of Cimetidine?
confusion, hallucinations, restlessness or lethargy
MOA of Psyllium?
Acts like fiber
What antipsychotic can also be used for nausea?
Haloperidol (Haldol)
Adverse effects of laxative salts?
- **Dehydration: Substantial water loss
- Acute renal failure
- Sodium retention: Exacerbated heart failure, hypertension, edema
Prototype for Phenothiazines?
Prochlorperazine
Patient education for Omeprazole?
- Take PO but do not chew or crush.
- Take vitamin D and calcium supplements to reduce risk of fractures.
- Avoid abrupt discontinuation.
- Know s/sx of respiratory infections and hypomagnesemia.
- caution use with other Mg lowering meds like Thiazides and loop diuretics.
How can aluminum hydroxide cause hypophosphatemia?
has a high affinity for phosphate and by binding with phosphate, the drug can reduce phosphate absorption
Drug interactions with Lomotil?
CNS depressants
What is the only stimulant that acts on the small intestines (Group 1)?
castor oil
MOA of laxative salts?
Pull water into the small intestine to soften and enlarge the stool to promote expulsion.
What is the serotonin receptor antagonist anti-emetic prototype?
Ondansetron (Zofran)
What class does scopolamine belong to?
muscarinic antagonist
Misoprostol (Cytotec) uses?
only approved GI indication is prevention of gastric ulcers caused by long-term therapy with NSAIDs
Sucralfate uses?
duodenal ulcers
What should we monitor in a patient taking Omeprazole?
Screen Mg levels before administration.
What are the benefits of Imodium?
suppresses bowel motility and prevents all the fluid loss into the intestinal lumen
Contraindication for Ondansetron?
Long QT syndrome
Most effective class for inhibiting acid secretion?
PPIs
Patient education for Famotidine use?
-stop or limit the use of smoking, alcohol, antacids, ASA, and NSAIDs
Which group of laxatives is the most frequently abused by the gen pub?
Group 3
Famotidine belongs to which class?
H2 blockers
How do we reduce the risk of TD with use of Metoclopramide?
treatment should be as brief as possible using the lowest effective dose.
Why does milk of magnesium need to be avoided in renal impairment?
The only place we can lose magnesium is through our kidneys so magnesium may accumulate to high levels, causing signs of toxicity.
Can patient’s still take antacids with Famotidine?
Yes, but should separate by 1 hour
