Sodium nitroprusside (SNP) is a chemical compound with the formula Na2[Fe(CN)5NO]. It is a medication used to lower high blood pressure (hypertension) in a clinical setting. Sodium nitroprusside works by relaxing the blood vessels, allowing for increased blood flow and reduced pressure on the arterial walls. It is administered intravenously and is typically used in emergency situations to rapidly lower blood pressure, such as in cases of hypertensive crises.

Due to its potency and potential side effects, sodium nitroprusside is only used under medical supervision. It is an important tool in managing severe hypertension when other treatments are ineffective or when immediate blood pressure reduction is critical.