GI Flashcards
(22 cards)
What to monitor for in patients who are on long term lactulose therapy in chronic constipation
Electrolyte imbalances (hyponatremia/hypokalemia)
Fluid status and dehydration: dry mouth, dizziness, decreased u/o, hypotension
Bowel fxn/tolerance
Frequency and consistency of stools ? Abdominal pain/bloating
*some patients can have gas/bloating/cramping from fermentation of lactulose
Mechanism of action of loperamide
Agonist at MU receptors
Decrease fluid secretion
Increase fluid absorption
Decrease propulsive contractions
Increase segmenting contractions
Delays gastric emptying
Who should be consoled to not take calcium carbonate antacids
Hypercalemia, caution with renal impairment> may cause alkalosis
Many drug interactions: ASA, Benz, anticoagulants, phenytoin, digoxin, nitrofuratonin, TSA, fluroquinolones, synthroid, histamine receptor antagonist, phenothiazines
Minimum safe age of prescribing loperamide/imodium in children
Minimum safe age is 2 years old
Children under 2 not safe> risk of milieus, respiratory depression and death
Children 2-5 only give if under medical supervision
WHo should avoid H2 receptor antagonist:
who should avoid:
Elderly patients due to increased risk of delirium and cognitive impairment
Renal impairment
Patients on multiple meds especially cimetidine CYP450 interactions
Patients with history of severe liver disease
MOA H2 receptor antagonist
MOA: bind to histamine 2 receptors on gastric parietal cells to reduce gastric acid secretion, slower onset than antacids but better at decreasing severity and frequency of heartburn symptoms
Decrease both basal and stimulated acid secretion making them effective for conditions like GERD, PUD and Zollinger-Ellison syndrome
H2 receptor onset of actions
onset of action: is slower or faster than antacids? slower
PPIs have slower action compared to H2 blockers
H2 receptor antagonists start working within 1 hour while PPIs take 1-4 days for full effect
PPIs provide loner acting acid suppression (up to 48 hrs) whereas H2 blockers work about 12 hours
Which H2 receptor antagonist has highest likelihood of interacting with CYP 450 system
tagamet/cimetidine
Which GERD treatment to avoid using in patients who have a history of pernicious anemia and vitamin B12 deficiency
PPIs
Which antacids have the greatest neutralizing capacity
Suspensions have greater neutralizing than powders/tabs- maalox
How probiotics work
Enhancement of epithelial barrier and increase adhesion to gut mucous
Not strictly repopulation of gut> stimulate phagocytes, increase IgA, activate CD4 and helper T cells
* promote gut balance, support immune system, promote regular BM, help bowel transit time
Which medications, food and drinks can decrease lower esophageal tone
Drugs: anticholinergics, caffeine, CCB, estrogen/progesterone, nicotine, nitrates, theophylline, tricyclic antidepressants
Food/drink: alcohol, citrus, tomato products, chocolate, spicy foods, peppermint, fatty foods, onions, garlic
Important counseling points for PPI
Metabolized by CYP450, taken daily for specific period of time, increased rate of bacterial infections (esp diff), PNA, Functions, CKD, dementia
Education: dont crush/chew, take prior to breakfast, long term users need taper
Which OTC can be used to help treat pt with mild traveler diarrhea
Loperamide
Antihistamines/anticholinergics: Dramamine, hydroxyzine, meclizine, promethazine, scopolamine
MOA: block physiological action of histamine (H1)/acetycholine at the receptor site > interrupts visceral afferent pathways that are responsible for stimulating n/v reflux
Indications: motionsicknessm vertigo, pregnancy
SE: dry mouth, constipation, urinary retention, blurred vision
Avoid alcohol, caution with glaucoma
Dopamine Antagonists
Centrally acting: phenergan, compazine
MOA: inhibit dopamine receptors in chemoreceptor trigger zone and neuroleptic (depresses nerve function)
ADR: blurred vision, dry mouth, dizzy, restless, seizure, EXTRAPYRAMIDAL
Peripherally acting: Reglan
MOA: inhibit dopamine in chemoreceptor trigger zone, block vagus nerve in GI system resulting in stimulation of GI motility
BLACK BOX warning: Tardive dyskinesia, QT prolong
Serotonin Antagonists (5HT3) > Zofran
SE: h/a, constipation, LFTs (if regular use), prolonged QT
Misaprostol has indication to treat ulcer caused by specific type of ulcer
NSAID ulcers
Warning associated with PPI use
Black Box: plavix with omeprazole > decrease antiplatelet effect
Caution: avoid longer term use can cause rebound heartburn and malabsorption of nutrients
Avoid in elderly for >8 weeks
Common side effects bismuth
Black stools & tongue, Toxicity: tinnitus
MOA of PPI
Block acid secretion by irreversibly binding to and inhibiting the hydrogen potassium ATPase Pump in the parietal cell membrane
Different types of laxatives and common side effects
Bulk: Metamucil, methycellulose, fiber con, bran
First line therapy for constiaption in adults, make sure drink plenty of water
Emollints/surfactants: colace, surfak
Stool softeners
Stimulants: dulcolax, senokot, castor oil
Constipation r/t decrease mobility, not recommended long term can lead to dependence
Saline lax: milk of mag, epsom salt, mag citrate, fleets
SE: dehydration, renal failure, electrolyte imbalance, hypermagnesemia
Hyperosmolar/osmotic lax: lactulose, sorbitol, glycerin, miralax
Electrolyte imbalances> phos, K, mg
