GI pharm Flashcards Preview

GI-Kevin > GI pharm > Flashcards

Flashcards in GI pharm Deck (12):

Antacids: which are absorbable and adverse affects? non absorbable? characteristics?

Mg (diarrhea), Al (constipation), Ca (constipation) based.
NaHCO3 (alkalosis) based.
Rapid onset and short duration


H-2RAs: suffix? mechanism? when should they be taken?

-tidine. competitive inhibition. Taken before bedtime (NO EATING afterwards b/c food signal can overcome blockade)


H2RA drug interactions

cimetidine inhibits CYP450 (relevant for phenytoin, warfarin, theophylline b/c of narrow therapeutic window)


PPIs: suffix? mechanism? side effects?

-prazole. Taken up by parietal cell, protonated, excreted, covalent bond with H/K ATPase (body must make new pump to regain secretion).
Slight risk of C. diff


PPI: drug interactions

Omeprazole weakly interacts with phenytoin, warfarin, diazepam, CLOPIDOGREL


What do you use PPIs for?

GERD, as part of H. pylori triple therapy (PPI, clarithromycin, amoxicillin), peptic ulcers (idiopathic, NSAID related), bleeding ulcer


sucralfate: complications

problematic in pts with renal insufficiency due to Al. Works at acidic pH (don't give with PPI, H2RA)


Alosetron: what is it? what do you use it for? why was it withdrawn?

5-HT3 antagonist. Used to tx women with SEVERE IBS-D.
Ischemic colitis, constipation, death


Drugs that cause constipation

verapamil, sucralfate, Ca or Al based antacids


Linaclotide: who not to give it to

Children under 6.


How to treat opioid constipation

peripheral mu antagonists: methylnaltrexone, alvimopan


Sulfasalazine: mechanism of activation and action. Used to treat?

split by colonic bacteria into sulfapyridine (toxic) and 5-ASA which has local anti-inflamm effects for ulcerative colitis