A woman receiving magnesium sulfate infusion for severe pre-eclampsia is also prescribed nifedipine for recurrent blood pressure spikes. Combining these two drugs raises concern primarily for which complication?

• A Severe bradycardia requiring pacing
• B Additive neuromuscular blockade causing respiratory depression
• C Acute hepatic necrosis
• D Precipitous fall in blood pressure causing placental hypoperfusion ✓

Explanation

Both agents are vasodilators, and their combination can cause abrupt, profound hypotension that compromises uteroplacental perfusion. Older literature also warned of potentiated neuromuscular blockade, but large series have shown the combination is generally safe when doses are appropriate, making symptomatic hypotension the practical concern monitored at the bedside rather than respiratory depression.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.