gi drugs Flashcards
misoprostol: MOA and adverse
inhibit adenylate cyclase in parietal cells, thereby decreasing acid secretion (recall that h2 receptor signals through CAMP pathway in parietal cell); adverse: uterine contractions, diarrhea
sucralfate
aloh3+sulfated sucrose to polymerize in presence of acid to cover epithelium/ulcer crater, and induce release of PGs. Rarely used. Adverse: can release aluminum and cause constipation (aluminum causes constipation)
colloidal bismuth
prevents diffusion of h+ to the mucosa. bacteriocidal also. travelers diarrhea and h pylori; adverse: black tongue, black stools, tinnitus
tx of h pylori
omeprazole, amoxicillin, clarithromycin
side effects of CaCO3, AlOH3, MgOH2
CaCO3: hypercalcemia, rebound acid
aloh3: constipation, hypophosphatemia, renal
mgoh2: diarrhea, hyporeflexia, renal
metoclopramide moa and adverse
D2 antagonist (inhibits gastric smooth muscle relaxation/LES relaxation) and 5HT4 agonist (increase cAMP) ultimately causing increased intestinal mobility adverse: tardive dyskinesia, extrapyramidle
erythromycin MOA and adverse
mimics motilin, increasing LES pressure, contractility of small bowel and stomach but not colon
adverse: qt prolongation
which H2 receptor antagonist is assoc. with cyp 450 induction and gynecomastia?
cimetidine
loperamide
diphenoxylate atropine (lomotil)
anti diarrhea mu opioid agonists (decrease intracellular cAMP); increase muscle tone; reduce peristalsis
alosetron
tx for diarrhea via 5ht3 antagonism. rare: ischemic colitis
lubiprostone moa
prostaglandin analogue: stimulates AC to make cAMP and activate chloride channel. (like cholera); treats constipation
linaclotide
guanylate cyclase agonist increases cGMP, leading to secretory anions and h2o. also helps pain bc extraceullar cGMP modulates nerves.
alvimopan
mu opioid antagonist to cause ultimate raising of cAMP.. given to tx postop ileus
methylnaltrexone
opioid induced constipation tx. mu opioid antagonist.
