GI I - Acid Peptic Diseases and GERD Flashcards
Key pathogenic agent in peptic ulcers? Functions?
H. Pylori is the key pathogenic agent and it both stimulates acid secretion and destroys stomach protective mechanisms
3 main drug categories to treat peptic ulcers
Druge that:
a. Decrease acid secretion
b. Neutralize stomach acid
c. Promote mucosal defence against acid
3 stomach cells and what do they secrete?
a. Enterochromaffin-like cell: histamine
b. Parietal cell: stomach acid
c. Superficial epithelial cell: cytoprotective mucus and bicarbonate
Histamine antagonists:
- What receptor?
- Functions?
Histamine antagonists:
- H2 receptor
- Blocks histamine but also blocks the potentiated actions of histamine and causes reduces secretion of acid
Prostaglandins:
- What two prostaglandins are important?
- What is their function?
- Agonist?
- Antagonist?
Prostaglandins:
- PGE2 and PGI2
- Protection: stimulate production of mucin and bicarb.
- Misoprostol
- NSAIDS
4 types of drugs with their role in the gastric lumen and role?
a. Proton pump inhibitors
b. Antacids: “soak up” H+ ions
c. H. Pylori medications
d. Cryoprotection: stimulate mucin and HCO3-
Proton Pump Inhibitors:
- These are ___ that require activation in an ___ environment.
- Type of binding? Duration?
- Most ___ suppressors. Reduce by what %?
Proton Pump Inhibitors:
- These are prodrugs that require activation in acid
- Covalent and irreversible binding; long duration of action
- Most potent suppressors. Reduce by 80-95%
Proton Pump Inhibitors:
Drugs?
Proton Pump Inhibitors:
a. Omeprazole
b. Esomeprazole
c. Rabeprazole
d. Lansoprazole
e. Pantoprazole
Proton Pump Inhibitors:
Conversion of drug to a ____ in the acidic secretory canaliculi of the ___ cell. The ___ interacts covalently with ___ groups in the proton pump, thereby ___ inhibiting its activity.
Proton Pump Inhibitors:
Conversion of drug to a sulfenamide in the acidic secretory canaliculi of the parietal cell. The sulfenamide interacts covalently with sulfhydryl groups in the proton pump, thereby irreversibly inhibition its activity.
Proton Pump Inhibitors:
Therapeutic uses?
Proton Pump Inhibitors:
a. Promote healing of ulcers
b. Treat GERD
c. Treat erosive esophagitis
d. Treat pathological hypersecretory conditions (Zollinger-Ellison)
e. Reduce risk of duodenal ulcers with H. pylori infection
Proton Pump Inhibitors:
- Lansoprazole specific FDA approval for?
- Omeprazole is safe and effective for treatment of ____ ___ and ___ in who?
Proton Pump Inhibitors:
- Lansoprazole - treatment and prevention of recurrence of NSAID-associated gastric ulcers
- Omeprazole is safe and effective treatment of erosive esophagitis and GERD in CHILDREN
Proton Pump Inhibitors:
General side effects?
Significant-ish side effect?
Proton Pump Inhibitors:
SE: nausea, abdominal pain, constipation, flatulence, and diarrhea
Significant: Hypergastrinemia - rebound hyperacidity and tumors
Proton Pump Inhibitors:
Drug interactions: what drugs?
Proton Pump Inhibitors:
Interaction with warfarin, diazepam, and cyclosporine
Proton Pump Inhibitors:
What drugs cannot be combined with warfarin?
Proton Pump Inhibitors:
Omeprazole, esomeprazole, rabeprazole, lansoprazole
Proton Pump Inhibitors:
What drugs cannot be combined with diazepam?
Proton Pump Inhibitors:
Omeprazole and esomeprazole
Proton Pump Inhibitors:
What drugs cannot be combined with cyclosporine?
Proton Pump Inhibitors:
Omeprazole and rabeprazole
H2 receptor antagonists:
- Interaction with H2 receptor? What membrane?
- Suppress secretion by ___%.
- Predominantly inhibit? When is this good?
H2 receptor antagonists:
- Reversible competitive inhibition on the basolateral membrane
- Suppress secretion by 70%
- Predominantly inhibit basal acid secretion - good during sleep
H2 receptor antagonists:
Drugs?
H2 receptor antagonists:
a. Cimetidine
b. Rantidine (most common)
c. Famotidine (most common)
d. Nizatidine
H2 receptor antagonists:
Therapeutic uses? (3)
H2 receptor antagonists:
Therapeutic uses:
a. Promote healing of ulcers
b. Treatment of uncomplicated GERD
c. Prevention of stress ulcers