Scopolamine is preferred over atropine for motion sickness because of which pharmacological property?
- A Greater potency at peripheral muscarinic receptors
- B Central anticholinergic action at the vestibular nuclei and vomiting center ✓
- C Longer half-life due to enterohepatic recirculation
- D Selective M2 receptor blockade in the heart
Correct answer: B. Central anticholinergic action at the vestibular nuclei and vomiting center
Explanation
Scopolamine crosses the blood-brain barrier and exerts central anticholinergic effects at the vestibular nuclei and the chemoreceptor trigger zone, which is why it is effective for motion sickness and vomiting. Atropine has less central penetration at usual doses. Scopolamine is not more peripherally potent and does not have M2 selectivity.
Reference: Katzung Basic and Clinical Pharmacology, 15th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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