GI deck 4 Flashcards
Prokinetics MOA
Stimulate motility of the GI tract without stimulating gastric, biliary, or pancreatic secretions
Prokinetic drug
Metoclopramide
Metoclopramide phamacodynamics
Metoclopramide stimulates motility in the upper GI tract.
Metoclopramide also has some actions similar to the phenothiazines and dopamine antagonists.
Metoclopramide has a
Black Box warning due to risk of developing tardive dyskinesia.
Prokinetics are contraindicated in
gastrointestinal (GI) hemorrhage, mechanical obstruction, new surgery on the GI tract, or perforation.
prokinetics use cautiously in
patients with a history of depression.
Depression may occur, including suicidal ideation.
porkineitcs are used more on a
short term basis
Prokinetics ADR
Tardive dyskinesia Depression, dizziness Diarrhea Hypoglycemia in patients with diabetes Rare: galactorrhea, amenorrhea, gynecomastia, impotence secondary to hyperprolactinemia
Prokinetics Additive ___
CNS depression occurs when used with other CNS depressants.
Prokineticcs increased risk of
EPS occurs with other drugs that have the potential for EPS.
Prokineitcs drugs with
anticholinergic effects reverse the action of metoclopramide.
Prokinetics clinical use and dosing
GERD
Adults: 10 mg 30 minutes before meals
Diabetic gastroparesis
10 mg 30 minutes before meals and at bedtime for 2 to 8 weeks
In patients with continuous complete remission below 40 mL/minute, their therapy initiated at approximately half the recommended dosage
Prokinetics monitoring
Renal function
New-onset movement disorder
Depression or suicidal ideation
Prokineitcs patient education
Administration
Take 30 minutes before meals.
Do not double doses.
Prokinetics ADR
Drowsiness
Additive CNS depression when taken with CNS depressants (alcohol)
Reporting any involuntary movements
Prokinetics lifestyle managment
GERD related lifestlyle changes
PPI (proton pump inhibitors) are
Drowsiness
Additive CNS depression when taken with CNS depressants (alcohol)
Reporting any involuntary movements
PPI are used for
erosive gastritis, GERD, and Zollinger-Ellison syndrome and as part of a treatment of active PUD, especially duodenal ulcers caused by Helicobacter pylori
PPI MOI
Reduce H+ secretion by inhibition of the H+/K+/adenosine triphosphatase (ATPase) enzyme system at the secretory surface of the parietal cell
Decrease in acid secretion lasts for up to 72 hours after each dose
PPI precautions and contraindications
Extensively metabolized in the liver; use cautiously in patients with hepatic dysfunction and in older adults
PPI pregnancy
category B or C
Congenital anomalies have been reported.
Use with caution.
PPI Children
Esomeprazole, omeprazole, and lansoprazole approved for short-term use in children as young as 1 year of age
Pantoprazole not approved in children 5 years of age and younger and rabeprazole not approved in children age less than 12 years
PPI ADR
Risk for significant nutrient deficiencies: iron, vitamin B12, and calcium
Long term PPI use increases
Long-term PPI use increases risk for osteoporosis and increased hip fractures
Long-term PPI therapy increases risk of Clostridium difficile, Salmonella, and Camphylobacter infections
PPI there is an increased
risk of pneumonia
PPI use questionable
gastric cancer risk
PPI causes
kidney injury chronic kideny disease
PPI Big picture
do not want them on it longer than 8 weeks. If longer than 8 weeks they should see a GI specialist
PPI decreases effectiveness of
of atazanavir, indinavir, and nelfinavir
PPI interfere with
absorption of drugs and depend on an acidic gastric pH to be effective
PPI incresed monitoring of
international normalized ratio (INR) if taken with warfarin
PPI with clopidogrel (plavix) has a
Black Box warning regarding interactions with omeprazole
PPI clinical use and dosing for duodenal and gastric ulcers
PPIs are combined with antibiotics to treat H. pylori.
PPI clinical use dosing for GERD
Used for 8 weeks, then patient weaned off
May need to double dose for 4 weeks and then decrease dose for another 4 weeks
PPI may mask the symptoms of
gastric cancers
PPI weaning
Decrease from twice/day to once/day, then every other day, with an H2RA used for symptoms, then patient weaned off.
Six classes of laxatives
Stimulants Osmotics Bulk-producing laxatives Lubricants Surfactants Hypoerosolar laxatives Chloride chanel activators Opioid receptor antagonists
Laxatives Stimulants MOI
direct action on intestinal mucosa by stimulating the myenteric plexus
Laxatives Osmotics MOI
draw water into the intestinal lumen
Bulk-producing laxatives: natural and semisynthetic polysaccharides and cellulose that mix with water in the intestine
Laxatives Lubricants MOI
soften stool and lubricates intestine
Laxatives surfactants MOI
reduce the surface tension of the oil–water interface on the stool and facilitate admixture of fat and water into the stool
Laxatives hyperosmolar MOI
draws water into intestine
Laxatives chloride channel activators MOI
activate CIC-2 chloride channels in the GI tract to produce chloride-rich secretions that soften the stool
Laxatives opioid receport antagonits MOI
mu receptor antagonists
Laxatives all are contrindicated in the
the presence of nausea, vomiting, or undiagnosed abdominal pain or if bowel obstruction is suspected or diagnosed
Magnesium hydroxide contraindicated
renal dysfunction
methylneltrexone may cause
opioid withdrawl
laxatives ADR
Excessive bowel activity, cramping, flatulence, and bloating
Laxative rapid short term use
Stimulants are the drugs of choice.
Osmotic laxatives also work well (magnesium hydroxide, PEG 3350).
Surfactants: docusate
Laxative slower response
Bulk-forming laxatives
Laxative for pregnancy
Bulk-forming laxatives are safest.
PEG (Miralax) or docusate may be used.
Laxative rapid actving administration
Rapid-acting laxatives are best taken in the morning; slower-acting ones are best taken at bedtime.
Laxative what is KEY
Prevention is the key.
Laxatives are temporary fixes.
Misconceptions about bowel function should be corrected.
