A powerful vasodilator, which refers to the widening of blood vessels, sodium nitroprusside is often used in helping patients with high blood pressure or Hypertension. Sodium nitroprusside is often injected directly into the blood vessels of people with high blood pressure as it is an effective treatment procedure for this condition.

Inside the blood vessels sodium nitroprusside decomposes and releases chemical substances which relax the vascular muscles.  When this happens there is less resistance in the blood vessels and thus lowers the rate of blood flow. As a result the pressure stretching across the ventricle of the heart, also known as preload, decreases. This action helps ease the rate of flow of blood and thus decreases the high blood pressure.

Apart from its benefit to people with the conventional hypertension, sodium nitroprusside is also an effective treatment for people with malignant hypertension, which is a complicated version of blood pressure mostly because of its extremely high level. It is also used to keep blood pressure under control during surgery.