Which of the following is a commonly used IV drug for malignant hypertension?

• A. Enalapril
• B. Labetalol
• C. Hydralazine
• D. Nitroprusside

Answer: (D)

In malignant hypertension, you need rapid but controlled lowering of blood pressure with an IV agent. Nitroprusside is used most often because it acts immediately and has a very short half-life, allowing precise titration to reach the target BP quickly without overshooting. It dilates both arteries and veins, so it reduces systemic vascular resistance and venous return, producing a fast, controllable drop in blood pressure—essential when there’s ongoing end-organ risk. This drug requires continuous arterial BP monitoring and careful adjustment of the infusion rate. Watch for potential toxicities with prolonged use, such as cyanide and thiocyanate buildup, and protect the solution from light. While other IV agents like hydralazine, labetalol, or IV enalaprilat can be used in hypertensive emergencies, nitroprusside is the most commonly used for malignant hypertension due to its rapid, titratable effects.