Which intravenous agent is the treatment of choice for torsades de pointes with recurrent polymorphic ventricular tachycardia?

• A Amiodarone
• B Adenosine
• C Magnesium sulfate ✓
• D Procainamide

Explanation

Intravenous magnesium sulfate suppresses early afterdepolarizations that trigger torsades de pointes and is effective even when serum magnesium is normal. Amiodarone and procainamide prolong repolarization further and are contraindicated here because they would worsen QT prolongation. Adenosine acts at the AV node and does not treat ventricular arrhythmias. Correction of the underlying cause such as hypokalemia or a culprit drug runs alongside magnesium therapy.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.