• Sodium nitroprusside is primarily used as a potent vasodilator.
  • Works predominantly in arterioles and venules as a result of its breakdown to nitric oxide (NO).[1]
  • Nitric oxide reduces both total peripheral resistance and venous return, thus decreasing both preload and afterload
  • Thiocyanate level when checking for toxicity

Adult Dosing

  • Start 0.5 mcg/kg/min IV, increasing 0.5 mcg/kg/min q5 min
  • Usual dosage 3-4 mcg/kg/min IV
  • Max dose 10 mcg/kg/min for 10 min

Pediatric Dosing

  • Start 0.3 mcg/kg/min IV, max 10 mcg/kg/min for 10 min


  • Pregnancy
  • ICH - theoretical concern for raising ICP via cerebral vasodilation, consider nicardipine instead[2]
  • Aortic coarctation
  • Arteriovenous shunt
  • Existing cyanide toxicity
  • High output heart failure
  • Lack of arterial line monitoring

Maximum Dose Rate

  • Infusion at maximum dose rate of 10 mcg/kg/min should never last for more than 10 minutes
  • If blood pressure is not controlled after 10 minutes of infusion at max rate, immediately terminate infusion


Mechanism of Action

Potent arteriolar dilation from its active metabolite, nitric oxide (NO).

Adverse Drug Reactions


  • Cyanide and thiocyanate metabolites potentially toxic
  • Metabolized via liver CYP450, excreted via urine
  • Half life 2 min
  • However, thiocyanate half life is 3 days

See Also

  1. "nitroprusside sodium (Rx) - Nipride, Nitropress, more..". Medscape Reference. WebMD. Retrieved 20 November 2013.
  2. Suri MF et al. A multicenter comparison of outcomes associated with intravenous nitroprusside and nicardipine treatment among patients with intracerebral hemorrhage. Neurocrit Care. 2009;11(1):50-5. doi: 10.1007/s12028-009-9192-1. Epub 2009 Feb 18.