Sucralfate binds to proteins at the ulcer base to form a protective barrier. Which drug interaction is clinically significant due to sucralfate's mechanism of action?
- A It reduces absorption of phenytoin, ciprofloxacin, and levothyroxine if given simultaneously ✓
- B It induces CYP3A4 and reduces serum levels of cyclosporine
- C It chelates calcium and enhances bisphosphonate absorption
- D It alkalinizes urine and increases excretion of amphetamine
Correct answer: A. It reduces absorption of phenytoin, ciprofloxacin, and levothyroxine if given simultaneously
Explanation
Sucralfate is a basic aluminum salt of sulfated sucrose that polymerizes and binds to proteins at the ulcer site. It also binds several drugs in the GI tract when co-administered, reducing their absorption. Phenytoin, fluoroquinolones, levothyroxine, and ketoconazole absorption are all impaired. Dosing should be separated by at least 2 hours.
Reference: Goodman and Gilman's The Pharmacological Basis of Therapeutics, 14th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.