A 70-year-old man with diabetic gastroparesis needs a prokinetic but developed acute dystonia when given metoclopramide previously. Which drug achieves gastric prokinetic effect without crossing the blood-brain barrier?
- A Domperidone ✓
- B Haloperidol
- C Ondansetron
- D Neostigmine
Correct answer: A. Domperidone
Explanation
Domperidone is a peripheral dopamine D2 antagonist that enhances gastric motility and antiemetic tone but does not cross the blood-brain barrier appreciably, so extrapyramidal effects and tardive dyskinesia are largely avoided. Metoclopramide crosses the BBB and blocks central D2 receptors, causing dystonia and parkinsonian features. Ondansetron is antiemetic but not prokinetic, and neostigmine increases overall gut tone without selective gastric emptying benefit.
Reference: Katzung's Basic and Clinical Pharmacology, 16th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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