2.11 GI Pharm: GERD, Ulcers, Gastroparesis Flashcards
What is the general MOA of antacids or ionic salts?
Weak bases that react to gastric acid H+ to neutralize them
Who should avoid using antacids?
People with renal insufficiency or drugs that need acidic environments like tetracyclines or FQ
What kind of monitoring do you need to do with patients taking antacids?
Electrolyte imbalance and renal function
What are antacids used to treat?
Mild GERD and occasional heartburn
NOT ulcers
What antacids salt ADSE include diarrhea or hyper magnesia that can lead to renal insuffiency?
Magnesium salts
What antacid slat can lead to hypercalcemia, alkalosis, or milk-alkali syndrome?
Calcium salt
What antacid salt ADSE includes constipation, neurotoxicity, hypophosphatemia, and anemia in renal failure?
Aluminum salts
What is the MOA of cimetidine, famotidine, ranitidine (“-idine”)?
H2 receptor antagonist (on parietal cells) reducing gastric acid secretion
What are cimetidine specific ADSE?
Gynecomastia, galactorrhea, CYP450 interactions
Although rare, what are the side effects of a competitive H2 receptor antagonist?
Headache, diarrhea, fatigue
What are the contraindications for cimetidine, famotidine, ranitidine?
Pregnancy (cross placenta)
What monitoring should you do for patients on H2 receptor antagonist?
Mental status (if IV) or drug interactions (cimetidine)
What are the “-tidine” H2 receptor antagonists used to treat?
GERD, peptic ulcer, mild acid reflux
What are the PPI drugs?
Omeprazole, lansoprazole, esomeprazole
“-prazoles”
What is the MOA of “-prazoles”?
Irreversible inactivate H+/K+ ATPase parietal cells
What is the specific ADME for PPIs?
Enteric coated activated in acidic environments
Take 1 hr before meal
What ADSE should you consider for PPIs?
Diarrhea, headache, decreased B12 absorption, hypomagnesia, acid rebound, infection risk
What should you avoid in patients taking omeprazole, lansoprazole, and esomeprazole?
Caution long term use (osteoporosis, hypomagnesia)
Avoid with CYP2C19 drugs (clopidogrel)
What do you monitor with patients taking the “-prazoles”?
Magnesium levels and infection signs
What do you use to treat GERD, peptic ulcers, H. Pylori infections, and NSAID-induced ulcers?
PPIs “-Prazole” drugs
Omeprazole, lansoprazole, esomeprazole
What are some mucosal protective agents you can use?
Sucralfate, Bismuth, Misoprostol
Sucralfate MOA?
Has aluminum that reduces pepsin access creating protective barrier on ulcers promoting healing
What is used to treat GERD in pregnancy?
Sucralfate
What is a Sucralfate ADSE?
Constipation (aluminum)
Can cause black stool, darken the tongue?
Bismuth
What are the contraindications for Bismuth?
Pregnancy and renal insufficiency
What is the MOA or bismuth?
Enhances prostaglandin production, binds to ulcer craters, and antimicrobial effects to H. Pylori (salicylates)
What is used to prevent NSAID ulcer damage?
Misoprostol
Prostaglandin E1 analog that reduced acid secretion by decreasing cAMP?
Misoprostol
Misoprostol ADSE and CONTRA?
Diarrhea + cramping
NO to pregnancy
What is the triple therapy for H. Pylori eradication?
Clarithromycin, amoxicillin, PPI
What is the quadruple therapy for H. Pylori eradication?
Metronidazole, tetracycline, PPI, Bismuth
Clarithromycin MOA?
Macrolide inhibiting bacterial 50S ribosome
Amoxicillin MOA?
Penicillin derivative disrupting cell wall synthesis
Metronidazole MOA?
DNA damage with free radicals (anaerobic bacteria)
Tetracycline MOA?
Protein synthesis inhibitor bacterial 30S ribosome
What is metroclopramide used for?
GERD, gastroparesis, antiemetic
What are the ADSE for a prokinectic agent like metoclopramide?
CNS: restless, drowsy, extrapyramidal (tardive dyskinesia** with long term use)
What is the MOA for metoclopramide?
D2 receptor antagonist with some 5-HT4 agonist activity
(Increase GI motility and accelerate gastric emptying)
Where does metoclopramide act?
Brain (CNS) - dopamine receptors
It blocks the 5HT released from mucosal enterochromaffin cells
