Medicine & USMLE


GI Drugs
  1. Ondansetron
  2. Sucralfate
  3. Docusate (Stool Softener)
  4. Bulk Forming Laxatives (Psyllium, Methylcellulose)
  5. Osmotic Laxatives (Lactulose, PEG)
  6. Stimulant Laxatives (Senna, Bisacodyl)
  7. Antidiarrheals (Loperamide, Diphenoxylate-Atropine)
  8. Bismuth Subsalicylate
  9. Antacids
  10. Proton Pump Inhibitors (PPIs)
  11. H2 Blockers
  12. Metoclopramide
  13. Misoprostol
  14. Orlistat
  15. Octreotide


Sucralfate is a mucosal protectant that forms a protective layer over the walls of the gastrointestinal tract, which can be helpful in preventing and treating ulcers. Notably, sucralfate alters the absorption of other drugs taken by mouth, so it shouldn’t be taken at the same time as any other PO medications. Sucralfate is best taken on an empty stomach. It may cause constipation as a side effect in some patients.

Key Points

  • Sucralfate (Carafate)
    • Mechanism
      • Drug class: Pepsin inhibitor (Mucosal Protectant)
        • Combines with a protein to create a protective layer over the gastrointestinal wall, specifically to prevent or protect ulcers
    • Clinical Use
      • Ulcer Treatment and Prevention
        • Usually prescribed 1 hour before meals and at bedtime
        • Best on an empty stomach
    • Side Effects and Adverse Reactions
      • Drug Interactions
        • Alters absorption of other oral medications
        • Should not be given at the same time as other medications
      • Constipation
        • Most common side effect
      • Systemic side effects are usually very minor because the drug is not absorbed from the GI tract
        • Dry mouth
        • Headaches
        • Dizziness
        • Drowsiness