Lec 2 - GI Drugs Flashcards
Gastrin is released from ____ cells into the ____.
G, bloodstream
gastrin:
binds ___ cells via the ____ receptor, causing a release of histamine;
binds ____ cells, causing a release of acid;
which is the more important effect?
ECL, CCKb (more important);
parietal
Gastrin is release in response to _____ and _____
peptides, vagal stimulation
vagal effects:
ACH binds ____ receptors on ____ cells, causing an increase in acid release;
_____ binds G cells, causing gastrin release
M3, parietal;
GRP
Histamine is released from ____ cells. it binds ____ receptors, which are G __ coupled on parietal cells
ECL;
H2, s
what 2 endogenous molecules inhibit release of acid from parietal cells?
prostaglandins, somatostatins
Gi associated
what kind of pump releases acid? where are parietal cells located?
H+/K+ ATPase;
fundus and body of stomach
what kind of cell is somatostatin released from?
D cells
histamine activates a ___ dependent pathway. Ach and gastrin activate a ____ dependent pathway
cAMP, IP3/Ca2+
Antacids:
____ has a high neutralizing capacity; adverse effects include alkalosis and fluid retention
NaHCO3
MgOH2 has a ____ neutralizing capacity. the main side effect is ____
high, diarrhea
CaCO3 has a ____ neutralizing capacity. the main side effect is _____ syndrome, hypercalcemia, and nephrolithiasis
moderate, milk-alkali
AlOH3 has a high neutralizing capacity. adverse effects include ____ and hypo______
constipation, phosphatemia
simethicone (mylicon, phazyme) is a mild ____ that enhances release of ____.
surfactant; gas
H2 receptor antagonists end in “___”;
dine;
cimeti, raniti, famoti, nizatidine
H2 blockers are _____ antagonists. They reduce acid secretion in response to histamine, _____, and _____.
competitive, gastrin, Ach
which of the H2 blockers inhibits CYP enzymes and can cause thrombocytopenia? ( ie warfarin, phenytoin, sulfonylureas interaction)
cimetidine
cimetidine also has anti ___ effects. name 3 symptoms
androgenic;
gynecomastia, impotence, galactorrhea (due to prolactin)
proton pump inhibitors (PPIs) all end in “____”
prazole
ie omeprazole, lanso, esome, panto, dexlanso
PPIs are ____ that are activated by ___ pH; they are (irreversible or reversible) inhibitors
prodrugs, acidic;
irreversible
PPIs cause an increase in ____, which can result in ____ hypersecretion of gastric acids
gastrin; rebound
PPIs:
____ is a CYP2C19 inhibitor (warfarin, phenytoin, clopidrogel)
all cause a decrease in absorption of ___ and ____ due to increased gastric pH
omeprazole;
digoxin, ketoconazole
PPIs cause an increase risk of _____ infection and ____. they can cause _____
C diff, pneumonia;
osteoporosis
“Acid rebound” is more common with what type of drugs
H2 antagonists
____ polymerizes and forms a protective barrier at ulcer sites. it requires a _____ pH
sucralfate, acidic
can decrease abs of tetracycline, digoxin, phenytoin
_____ is a synthetic prostaglandin _ derivative. it causes decreased ____ secretion and increased _____ and ___ secretion
misoprostol, E1;
acid; bicarb, mucus
H. pylori causes a reduction in ____ cell production of ____ and an increase in secretion of ____
D, somatostatin;
gastrin
triple therapy typically used for H pylori:
amoxicillin (or metronidazole) + clarithromycin + PPI (or H2 blocker)
also bismuth salt
_____ is used in treatment of mild diarrhea and eradication of H pylori
bismuth subsalicylate`
____ is a D2 receptor antagonist
metroclopramide
blockade of D2 receptors in the myenteric plexus leads to increased _____ release. also has anti ___ effects
Ach;
emetic
metroclopramide:
used for post-surgery and _____ gastroparesis, ____, and anti-emesis
diabetic, GERD
side effects of metroclopramide:
____ effects, CNS ____, hyper_____
parkinsonian, sedation, prolactinemia (ie gynecomastia, galactorrhea)
what macrolide is prokinetic? it is a ____ agonist
eryrthromycin, motilin
cisapride, tegaserod, and prucalopride are all withdrawn from the market. they are ____ agonists
5-HT4
linaclotide is an activator of _____. it used used for ____, such as in IBS
guanylate cyclase 2, constipation
linaclotide:
increased intracellular ____ causes increased secretions and decreased ____
cGMP;
pain
sennam biscaodyl, cascara, and castor oil all stimulate ____. they open ___ channels in the intestinal mucosa to facilitate movement of ions and water into the intestinal lumen
peristalsis, Cl-
lubiprostone is a specific ___ activator. it is used for chronic ____, such as in IBS
Cl C2;
constipation
name 2 bulk laxatives, besides bran and milk of magnesia
psyllium, methycellulose
bulk laxatives are ____ fibers that draw water into the gut lumen, leading to ____ and ____
soluble;
distention, peristalsis
lactulose is a ____ laxative that is used to treat what disease?
osmotic, hepatic encephalopathy
MgOH, magnesium citrate, and polyethylene glycol are ____ laxatives
osmotic
____ is a stool surfactant that lubricates the lower bowell
docusate
dicyclomine is a _____. it treats diarrhea
anti-cholinergic
2 opiates typically used in diarrhea. which is given with atropine to prevent addiction?
diphenoxylate and loperamide;
diphenoxylate
anti-diarrheals are contraindicated in what 2 conditions?
inflammatory disease (ie ulcerative collitis); bacteria induced diarrhea
kaolin and pectin absorb potential intestinal ____ and water
toxins (ie anti-diarrheal)
_____ is indicated for patients with HIV/AIDS on retroviral therapy. it blocks ____ and Ca activated Cl channels
cofrelemer;
CFTR
aloesetron is a ____ receptor antagonist. it used used for women with chronic ___, such as in IBS
5HT3;
diarrhea
alosetron blocks visceral afferent ___ ____ and _____ colon motility
pain sensation, decreases
aloestron can cause fatal _____
ischemic colitis
3 systems that feed into the vomiting center. what is the vomiting center?
vestibular, area postrema, gastric receptors;
Nucleus tractus solitarius
in addition to metroclopramide, name 2 other D2 antagonists
promethazine, prochlorperazine
meclizine and _____ are anti-emetic via anti Ach effects
scopalamine
ondansetron (or granisetron) is a ____ receptor antagonist. they decrease ____ stimulation
5HT3, vagal
ondansetron is used to treat nausea and vomiting associated with ____. it is combined with ____, which is a NK1 antagonist
chemo;
aprepitant
dronabinol and nabilone are ______ aka synthetic _____
cannabinoids, THC
