GI Pharm 2 (esophagus, stomach, duodenum) Flashcards
Antacids:
- used for tx of?
- medication classes
- MOA
- drug interactions
Used for tx of ulcers!
Classes;
- aluminum salts
- Magnesium hydroxide
- calcium carbonate
MOA: of all antacids:
- neutralize gastric acid
- bind bile acids and inhibit peptic activity
- promote angiogenesis in injured mucosa
- heavy metals suppress H. pylori
Drug Interactions:
- interact with many abx
- can bind w/ drugs taken at the same time decreasing absorption of that agent.
Magnesium Salts:
- aka
- brand names
- common SE
- Cautions
aka: magnesium hydroxide/aluminum hydroxide
Brand names:
-maalox, alamoag, Mylanta
Common SE:
-diarrhea, constipation, abd cramps, N/V, hypermagnesemia
Caution w/ renal insufficiency
Aluminum Salts:
- cautions
- brand names
caution with renal insufficiency
brand names: Acid Gone, Gaviscon
Calcium Carbonate:
- brand names
- indications
- MC SE
- administration directions
Brands:
-tums, maalox regular chewable, calci-chew, Rolaids, Chooz, alka-mints
indications: acid indigestion, heartbrun
MC SE:
-constipation, bloating, gas, N/V, abd pain, xerostomia (dry mouth)
Admin directions: take separate from other meds by 2 hrs.
H2 Blockers
- drug names
- indications
- MOA
- administration directions
- SE
Drug name:
- Cimetidine (Tagamet)
- Ranitidine (Zantac)
- Famotidine (Pepcid)
- Nizatidine (axid)
indications:
- tx of PUD, GERD, dyspepsia
MOA:
-inhibit acid secretion by blocking histamine H2 receptors on the parietal cell
Directions:
-take 30-60minutes prior to meal (if using for acid suppression w/ meals)
SE:
- rare severe adverse events such as renal and hepatic toxicity
- Myelosuppression:
- -thrombocytopenia
- -neutropenia
- -anemia
- -pancytopenia
- reversible if taken off H2 blockers.
- rare CNS SE: confusion, HA, dizziness, agitation, w/ prolonged therapy hallucinations, focal twitching, seizures, unresponsiveness, and apnea.
- rare cardiac SE: sinus bradycardia, hypotension, AV block, prolonged QT, sinus and cardiac arrest have occurred with RAPID infusion.
Cimetidine SE
- rarely causes gynecomastia and impotence
- polymyositis
- interstitial nephritis
- cleared through P450 system so had multiple drug interactions
- rapid admin can cause arrhythmias and hypotension
*probably dont want to use this one because of all the nasty SE.
H2 Blockers:
-absorption and distribution
- well absorbed after oral dosing
- peak serum concentration occur within 1-3hrs
- absorption is reduced by 10-20% if taken with antacids.
Proton Pump Inhibitors
- brand names
- indications
- MOA
- administration directions
- onset and peak of action
brands:
- Omeprazole (Prilosec)
- Lansoprazole (Prevacid)
- Pantoprazole (Protonix)
- Esomeprazole (Nexium)
- Dexlansoprazole (Kapidex)
- Rabeprazole (AcipHex)
indications:
- tx of all acid related disorders
- -PUD, GERD, Zollinger-Ellison syndrome, NSAID associated gastroduodenal mucosal injury, eradication of H, pylori
MOA:
-blocks acid secretion by irreversibly binding to and inhibiting the H+/K+ ATPase pump on the parietal cell membrane.
Admin directions:
-amount of H/K ATPase present in the parietal cells is greates after a prolonged fast, PPI’s should be administered 30-60min BEFORE the first meal of the day. If second dose needed take it 30-60 mins prior to the last meal of the day.
Onset: 1 hr
Peak: 2hrs
PPI:
- SE
- which have the highest and lowest drug interactions
SE:
- diarrhea
- HA
- flatulence with protonix
Drug interactions:
- Protonix has LOWEST potential for P450 drug interactions
- Omeprazole (prilosec) and Esomeprazole (Nexium) metabolize through CYP2C19 and have the GREATEST potential for drug interactions.
Can omeprazole and clopidogrel(plavix0 be taken at the same time?
No, there is a significant rxn between the two, BBB. Omeprazole inhibits clopidogrel and promotes clotting.
PPI:
-long term administration may increase incidence of?
infections: c. diff. PNA
fractures: hip, wrist, spine
malabsorption: B12, magnesium, iron
Sulcralfate (Carafate)
- aka
- MOA
- administration directions
- cautions
aka: sucrose octasulfate-aluminum hydroxide
MOA: creates protective barrier in the stomach, promotes healing through angiogenesis in the ulcer base.
Admin direction:
-take 30-60min before meals
Cautions:
-d/t combination with aluminum hydroxide do not administer with aluminum containing antacids in pts with renal failure
-do not administer with citrate containing cmpds; increases aluminum absorption by 50x in normal renal function
Bismuth:
- aka
- MC use
- MOA
aka: pepto-bismol
MC use is h pylori infection, not helpful in tx of non h. pylori induced ulcers.
MOA:
- inhibition of peptic activity but not pepsin secretion
- binds to ulcer craters
- recruits mfs to the edge of ulcer and promotes healing
- increase mucosal prostaglandin production and mucus bicarbonate secretion
Misoprostol (Cytotec)
- indications
- pregnancy category
- MOA
- BBW
indications:
- prevention and tx of NSAID induced ulcers
-pregnancy category X
MOA:
- prostaglandin E1 analog
- enhances mucosal defenses and promotes ulcer healing
BBW:
-during pregnancy causes abortion, birth defects, or premature birth.
Prokinetic
- drug name
- first line agent for what disorder?
- MOA
- SE
Drug name: metaclopramide
First line therapy for GASTROPARESIS no longer than 12 weeks unless benefits outweigh risks.
MOA: improves gastric emptying by increasing gastric antral contractions and decreasing postprandial fundus relaxation.
-dopamine receptor agonist, 5-HT4 agonist, weak 5-HT3 receptor antagonist
SE:
- anxiety
- restlessness
- depression
- hyperprolactinemia
- QT prolongation
- Dystonia*
- Tardive Dyskinesia*
