Nipruss (Sodium Nitroprusside Dihydrate)

Sodium nitroprusside is employed in cardiovascular care to rapidly lower blood pressure and manage acute cardiac conditions.

• Hypertensive emergencies: provides immediate reduction of severe arterial pressure.
• Acute heart failure: decreases preload and afterload to improve cardiac output.
• Controlled hypotension during surgery: maintains low blood pressure to reduce intra‑operative bleeding.

• Sodium nitroprusside releases nitric oxide upon intravenous administration. The nitric oxide activates guanylate cyclase in vascular smooth muscle, increasing cyclic GMP levels, which leads to relaxation of arterioles and venules. This vasodilation reduces both preload and afterload, producing a rapid fall in systemic blood pressure and facilitating controlled hypotension.

Sodium nitroprusside may cause a range of adverse reactions that vary in frequency and severity.

Common Side Effects

• Headache: mild to moderate pain often occurring shortly after infusion.
• Nausea: transient gastrointestinal discomfort.
• Flushing: warm sensation and reddening of the skin.
• Tachycardia: compensatory increase in heart rate.

Serious or Rare Side Effects

• Cyanide toxicity: accumulation of cyanide metabolites with prolonged use.
• Methemoglobinemia: oxidation of hemoglobin impairing oxygen delivery.
• Severe hypotension: excessive drop in blood pressure leading to organ hypoperfusion.
• Arrhythmias: irregular heart rhythms that may require monitoring.

When using Sodium nitroprusside, clinicians should observe specific safety measures.

• Continuous blood pressure monitoring: adjust infusion rate to maintain target pressure.
• Cyanide level assessment: especially during infusions longer than 24 hours.
• Dose adjustment in renal or hepatic impairment: reduced clearance may increase toxicity risk.
• Avoid in patients with known hypersensitivity to nitroprusside or its excipients.
• Use cautiously with concomitant thiol‑containing drugs that may increase cyanide production.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze or shake.

Sodium nitroprusside can interact with several agents, requiring attention to avoid adverse outcomes.

Major Interactions (Avoid)

• Sodium nitrite: combined use heightens cyanide formation.
• Thiol‑containing drugs (e.g., N‑acetylcysteine): increase cyanide load.
• Other nitric oxide donors (e.g., nitroglycerin): may cause profound hypotension.

Moderate Interactions (Monitor Closely)

• ACE inhibitors: additive blood‑pressure lowering effect.
• Diuretics: volume depletion can amplify hypotensive response.
• Beta‑blockers: may mask tachycardia that signals excessive vasodilation.