Question | Answer |
peptic ulcers are degrees of erosion of the gut wall the occur here | mostly duodenum, and stomach --> bleeding/perforation |
what causes peptic ulcers | imbalance between mucosal defenses and opposing aggressive factors |
name 5 aggressive factors | *H. pylori
*NSAIDs
*acid
*pepsin
*smoking |
Name mediator of defensive factor and 3 processes it manages for defensive factors | prostaglandin activation mediates mucous, bicarbonate and blood flow (all defensive factors) |
name classes of anti-ulcer drugs | *antacids
*antisecretory
*mucousal protectants
*Pg enhancement of mucosal defenses
*antibiotics |
Two types of antisecretory agents | *H2 Blockers
*PPIs |
bacteria that is 2nd most common infection in world --> peptic ulcer disease | H. pylori |
Antisecretory H2 blockers MOA | blocks histamine from binding H2 -->cAMP 2nd messenger --> thereby blocking proton pump |
another name for proton pump | H+/K+/ATPase pump (H+ to lumen, K+ exchanged into parietal cell) |
5 H2RA (H2 blocking) drugs | *cimetidine
*ranitidine
*famotidine
*nizatidine |
which drug is shortest acting with most SEs/interactions in H2 blocking class | cimetidine, which is Rx/OTC ---oral/inj |
pharmokinetics of cimetidine | hepatic CYP450 interactions, partially excreted in renal impaired (reduce dose in RF pts) |
ADRs of cimetidine | *endocrine - adrogeneric/estrogenic actions
*CNS - confusion, hallucinations, depression- all more likely in elderly, renal impaired |
do ranitidine, famotidine or nizatidine have endocrine or CNS SEs | not, they are well tolerated, few interactions |
cimetidine class | H2 blocker - shortest acting - most interactions |
ranitidine class | H2 blocker - also available IV |
famotidine class | H2 blocker - longest acting |
nizatidine class | H2 blocker - similar to ranitidine |
are H2 blocker drugs available OTC as well | yes, this class available OTC |
PPI = proton pump inhibitor (antisecretory)MOA | this ACID LABILE class must be enterically coated so it can survive stomach acid before being released into bloodstream in duodenum where it travels through vasculature to directly inhibit PP |
name 5 PPIs in class | *omeptrazole
*lansoprazole
*patoprazole
*rabeprazole
*esomeprazole |
ADRs of PPIs | HA, A, N, D, V
*carcinogenic potential ONLY seen in animals |
which 2 PPIs are available OTC | *omeprazole, lansoprazole |
unusual feature about PPI half life | this class has short half-life that is unrelated to duration of action |
omeprazole class | PPI - oral only - rx/otc |
lansoprazole class | PPI - oral/IV - rx/otc |
patoprazole class | PPI - oral/IV |
rabeprazole class | PPI like others in class |
esomeprazole class | PPI - isomer of omeprazole |
MOA of mucosal protectant drug | non-antisecretory - forms topical protective layer that lasts 6 hours (QID admin) |
ADRs of mucosal protctant drug sucralfate | *constipation very common
*Al+++ component --> drug interactions |
name of mucosal protectant drug | sucralfate (carafate) |
drug class that enhances action of mucosal protectants | prostaglindins - non-antisecretory, act by increasing action of protective mechanisms |
misoprostol class | enhance mucousal protectant class |
misoprostol indicated for | prevention of NSAID induced gastric ulcer, as well as other applications from other chapters |
misoprostol MOA | exerts all protective effets that endogenous Pgs do for mucosal protection (+mucous, +bicarb, +blood flow). not-antisecretory |
serious ADR misoprostol | ABORTIFACIENT contraindicated in pregnancy |