Which agent is used to treat eclampsia and some cardiac emergencies?

• A. Fentanyl
• B. Adenosine
• C. Magnesium sulfate
• D. Vaccines

Answer: (C)

Magnesium sulfate is used because it both prevents and treats seizures in eclampsia and helps stabilize certain dangerous heart rhythms, making it the only option that fits both scenarios. In eclampsia, magnesium raises the seizure threshold and calms neural excitability, which is why it’s given to prevent and treat seizures in pregnancy-related hypertensive crises. In cardiac emergencies, it is the first-line treatment for torsades de pointes, a type of ventricular tachycardia linked to QT prolongation; magnesium stabilizes myocardial membranes and reduces abnormal electrical activity that drives this rhythm.

Understanding the other options helps solidify why this one fits. Fentanyl is an opioid pain reliever, not used to prevent seizures or treat torsades. Adenosine is used to acutely terminate certain fastheart rhythms like SVT, not for eclampsia or torsades. Vaccines have no role in treating seizures or acute cardiac arrhythmias.