What is the drug of choice for seizure prophylaxis in preeclampsia?

• A. Magnesium sulfate
• B. Phenytoin
• C. Diazepam
• D. Levetiracetam

Answer: (A)

Prevention of seizures in preeclampsia is crucial because seizures dramatically worsen outcomes for both mother and baby. Magnesium sulfate is the standard choice because it has strong, consistent evidence showing it reduces the risk of progression to eclampsia in women with preeclampsia, including those with severe features, and it has a long track record of safety in pregnancy. The typical approach uses an IV loading dose of 4–6 g, followed by a continuous infusion of 1–2 g per hour, with careful monitoring of deep tendon reflexes, respiration, and urine output to catch signs of toxicity early. If toxicity occurs—such as absent reflexes or respiratory depression—the infusion is stopped and calcium gluconate is given as the antidote. While other anticonvulsants can be used for various seizure problems, magnesium sulfate remains preferred for seizure prophylaxis in preeclampsia due to its proven protective effect and favorable safety profile in pregnancy.