A 22-year-old woman is brought after ingesting amitriptyline. She has altered mental status, dry mucous membranes, and a widened QRS complex on ECG. The most appropriate specific therapy to prevent cardiac toxicity is:
- A Sodium bicarbonate ✓
- B Flumazenil
- C Naloxone
- D Magnesium sulfate
Correct answer: A. Sodium bicarbonate
Explanation
Tricyclic antidepressant overdose causes sodium channel blockade, leading to QRS widening and ventricular arrhythmias. Sodium bicarbonate alkalinizes the serum and provides a sodium load that overcomes the channel blockade, narrowing the QRS and stabilizing the myocardium. Flumazenil and naloxone are not indicated.
Reference: Katzung & Trevor's Pharmacology Examination and Board Review, 13th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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