GI DRUGS - CLASSES/MECHANISMS Flashcards
Cimetidine
H2 blocker: Reversible block of histamine H2-receptors → decreased H+ secretion by parietal cells
Ranitidine
H2 blocker: Reversible block of histamine H2-receptors → decreased H+ secretion by parietal cells
Famotidine
H2 blocker: Reversible block of histamine H2-receptors → decreased H+ secretion by parietal cells
Nizatidine
H2 blocker: Reversible block of histamine H2-receptors → decreased H+ secretion by parietal cells
Omeprazole
PPI: Irreversibly inhibits H+/K+ ATPase in stomach parietal cells
Lansoprazole
PPI: Irreversibly inhibits H+/K+ ATPase in stomach parietal cells
Esomeprazole
PPI: Irreversibly inhibits H+/K+ ATPase in stomach parietal cells
Pantoprazole
PPI: Irreversibly inhibits H+/K+ ATPase in stomach parietal cells
Dexlansoprazole
PPI: Irreversibly inhibits H+/K+ ATPase in stomach parietal cells
Aluminum hydroxide
Antacid
Calcium carbonate
Antacid
Magnesium hydroxide
Antacid
Osmotic laxative: Provides osmotic load to draw water into GI lumen
Bismuth
Bind to ulcer base, providing physical protection and allowing HCO3- secretion to reestablish pH gradient in the mucous layer
Require acidic environment
Sucralfate
Bind to ulcer base, providing physical protection and allowing HCO3- secretion to reestablish pH gradient in the mucous layer
Require acidic environment
Misoprostol
PGE1 analog: Increase production and secretion of gastric mucous barrier, decrease acid production
Octreotide
Long-acting somatostatin analog: Inhibits secretion of various splanchnic vasodilatory hormones
Sulfasalazine
Combination:
- Sulfapyridine (antibacterial)
- 5-aminosalicylic acid (anti-inflammatory)
Activated by colonic bacteria
Loperamide
Mu-opioid receptor agonist → slows gut motility
Diphenoxylate
Mu-opioid receptor agonist → slows gut motility
Meperidine
Mu-opioid receptor agonist → slows gut motility
Ondansetron
Powerful central-acting antiemetic:
5-HT3 antagonist
Decreases vagal stimulation
Granisetron
Powerful central-acting antiemetic:
5-HT3 antagonist
Decreases vagal stimulation
Metoclopramide
D2 receptor antagonist:
- Increases resting tone
- Increases contractility
- Increases LES tone
- Increases motility
- Promotes gastric emptying
Prochlorperazine
D2 receptor antagonist:
- Increases resting tone
- Increases contractility
- Increases LES tone
- Increases motility
- Promotes gastric emptying
Orlistat
Inhibits gastric and pancreatic lipase → decreases breakdown and absorption of dietary fats
Psyllium
Bulk-forming laxative: Soluble fibers that draw water into gut lumen, forming viscous liquid that promotes peristalsis
Methylcellulose
Bulk-forming laxative: Soluble fibers that draw water into gut lumen, forming viscous liquid that promotes peristalsis
Magnesium citrate
Osmotic laxative: Provide osmotic load to draw water into GI lumen
Polyethylene glycol
Osmotic laxative: Provide osmotic load to draw water into GI lumen
Lactulose
Osmotic laxative: Provide osmotic load to draw water into GI lumen
Lactulose
Stimulant laxative: Enteric nerve stimulation → colonic contraction
Docusate
Emollient: Osmotic draw into lumen → increase water absorption by stool
Aprepitant
Substance P antagonist → blocks NK1 receptors in brain (antiemetic for chemotherapy-induced N/V)
Dosaprepitant
Substance P antagonist → blocks neurokinin- 1 (NK1) receptors in brain (antiemetic for chemotherapy-induced N/V)