Sodium nitroprusside

Direct Vasodilator·Cardiovascular - Vasopressors & ICU

Hypertensive emergencies, controlled hypotension during surgery, acute heart failure

VASODILATORNipride50 mgS4TGA

Max Dose

10 mcg/kg/min

Half-life

<2 mins

Cyanide Tox

RISK

Route

IV ONLY

Rapid Summary

Overview

Ultra-short acting, intensely potent venous and arterial vasodilator. Breaks down in the blood to release Nitric Oxide and Cyanide.

Maximum Dose

Max 10 mcg/kg/min (Infusions > 2 mcg/kg/min carry high cyanide toxicity risk over time).

Clinical Focus

ICU/OT medication only. Requires an arterial line for continuous beat-to-beat blood pressure monitoring.

Bottom Line

Sodium nitroprusside is the most potent IV vasodilator for hypertensive emergencies, but requires arterial line monitoring and carries the risk of fatal cyanide toxicity with prolonged use.

Formulation & Access

Brand Names

Nipride

Parenteral

Ampoule (50 mg). Must be protected from light (wrapped in foil/opaque bag).

Prescribing & PBS

Restricted. Hospital supply only.

Indications & Use

Primary

TGA

Hypertensive emergencies, controlled hypotension during surgery, acute heart failure.

Clinical Place

When instant, rapidly titratable, profound afterload/preload reduction is required.

Quick reference

Class & Role

Direct Vasodilator — Ultra-short acting, intensely potent venous and arterial vasodilator.

Route / Formulation

Ampoule (50 mg). Must be protected from light (wrapped in foil/opaque bag). (Nipride)

Usual Dose & Max

IV Infusion Start 0.25–0.5 mcg/kg/min. Titrate strictly to BP response. Max 10 mcg/kg/min (for maximum 10 minutes).

Key Indication Doses

Hypertensive Crisis / Acute Heart Failure: IV Infusion Start 0.25–0.5 mcg/kg/min. Titrate strictly to BP response. Max 10 mcg/kg/min (for maximum 10 minutes). Renal Impairment: Avoid prolonged use; highly sensitive to thiocyanate accumulation.

Best Uses

Sodium nitroprusside is the most potent IV vasodilator for hypertensive emergencies, but requires arterial line monitoring and carries the risk of fatal cyanide toxicity with prolonged use.

Avoid / Cautions

Compensatory hypertension (e.g., severe A-V shunting or coarctation of the aorta), uncorrected hypovolemia, severe vitamin B12 deficiency. Pregnancy Category C. Fetal cyanide toxicity.

Key Risks

Cardiovascular: Profound, irreversible hypotension if overdosed. 'Coronary steal' syndrome in IHD. Toxicology: Cyanide toxicity (metabolic acidosis, coma, almond breath) and Thiocyanate toxicity (delirium, seizures, tinnitus). Haematological: Methaemoglobinaemia.

Key Interactions

PDE5 inhibitors (e.g., Sildenafil) cause catastrophic hypotension.

Monitoring

Intra-arterial BP line. Observe for signs of cyanide toxicity (unexplained metabolic acidosis, rising lactate). Frequent ABGs (lactate, pH). Monitor thiocyanate levels if infusion lasts > 48 hours.

Clinical Pearl

The IV bag and lines MUST be wrapped in foil or black plastic. Exposure to light breaks the drug down into cyanide directly in the bag.

Access

Nipride

Brand: Nipride

Sodium nitroprusside

Direct Vasodilator·Cardiovascular - Vasopressors & ICU

Hypertensive emergencies, controlled hypotension during surgery, acute heart failure

VASODILATORNipride50 mgS4TGA

Max Dose

10 mcg/kg/min

Half-life

<2 mins

Cyanide Tox

RISK

Route

IV ONLY

Rapid Summary

Overview

Ultra-short acting, intensely potent venous and arterial vasodilator. Breaks down in the blood to release Nitric Oxide and Cyanide.

Maximum Dose

Max 10 mcg/kg/min (Infusions > 2 mcg/kg/min carry high cyanide toxicity risk over time).

Clinical Focus

ICU/OT medication only. Requires an arterial line for continuous beat-to-beat blood pressure monitoring.

Bottom Line

Sodium nitroprusside is the most potent IV vasodilator for hypertensive emergencies, but requires arterial line monitoring and carries the risk of fatal cyanide toxicity with prolonged use.

Formulation & Access

Brand Names

Nipride

Parenteral

Ampoule (50 mg). Must be protected from light (wrapped in foil/opaque bag).

Prescribing & PBS

Restricted. Hospital supply only.

Indications & Use

Primary

TGA

Hypertensive emergencies, controlled hypotension during surgery, acute heart failure.

Clinical Place

When instant, rapidly titratable, profound afterload/preload reduction is required.

Quick reference

Class & Role

Direct Vasodilator — Ultra-short acting, intensely potent venous and arterial vasodilator.

Route / Formulation

Ampoule (50 mg). Must be protected from light (wrapped in foil/opaque bag). (Nipride)

Usual Dose & Max

IV Infusion Start 0.25–0.5 mcg/kg/min. Titrate strictly to BP response. Max 10 mcg/kg/min (for maximum 10 minutes).

Key Indication Doses

Best Uses

Sodium nitroprusside is the most potent IV vasodilator for hypertensive emergencies, but requires arterial line monitoring and carries the risk of fatal cyanide toxicity with prolonged use.

Avoid / Cautions

Compensatory hypertension (e.g., severe A-V shunting or coarctation of the aorta), uncorrected hypovolemia, severe vitamin B12 deficiency. Pregnancy Category C. Fetal cyanide toxicity.

Key Risks

Key Interactions

PDE5 inhibitors (e.g., Sildenafil) cause catastrophic hypotension.

Monitoring

Intra-arterial BP line. Observe for signs of cyanide toxicity (unexplained metabolic acidosis, rising lactate). Frequent ABGs (lactate, pH). Monitor thiocyanate levels if infusion lasts > 48 hours.

Clinical Pearl

The IV bag and lines MUST be wrapped in foil or black plastic. Exposure to light breaks the drug down into cyanide directly in the bag.

Access

Nipride

Brand: Nipride