A 30-year-old woman presents to the emergency department with confusion, flushed dry skin, urinary retention, dilated pupils, and sinus tachycardia after a suspected overdose of an anticholinergic drug. Which acetylcholinesterase inhibitor crosses the blood-brain barrier and is indicated to reverse central anticholinergic toxicity?

• A Neostigmine
• B Pyridostigmine
• C Edrophonium
• D Physostigmine ✓

Explanation

Physostigmine is a tertiary amine acetylcholinesterase inhibitor that crosses the blood-brain barrier, making it effective for central anticholinergic syndrome. Neostigmine, pyridostigmine, and edrophonium are quaternary ammonium compounds that do not cross the BBB and are ineffective for CNS symptoms.

Reference: Goodman and Gilman's The Pharmacological Basis of Therapeutics, 14th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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