sodium nitroprusside dihydrate: clinical use

Prescribing considerations

• Restricted to acute, closely supervised intravenous use; it is not suitable for permanent therapy.
• Use particular caution with increased intracranial pressure, hepatic impairment or renal impairment.
• Review recent phosphodiesterase-5 inhibitor exposure before administration.
• Follow the current product-specific cyanide-prevention and toxicity-management procedures.
• Safety and efficacy have not been established in children or adolescents.

Contraindications and cautions

• Hypersensitivity to sodium nitroprusside or the excipient
• Compensatory hypertension caused by conditions such as aortic coarctation or an arteriovenous shunt
• Leber hereditary optic atrophy
• Tobacco amblyopia
• Vitamin B12 deficiency
• Metabolic acidosis
• Hypothyroidism
• Intrapulmonary arteriovenous shunts

Monitoring

• Continuously monitor blood pressure, ECG and relevant haemodynamic variables.
• Watch for excessive hypotension and rebound effects.
• Monitor for cyanide toxicity, particularly with hepatic impairment or substantial exposure; clinical indicators include rising lactate, metabolic acidosis and impaired oxygen utilisation.
• Monitor thiocyanate where accumulation is a concern, particularly with renal impairment.
• Inspect the infusion solution and administration site; maintain light protection.

Clinical pharmacology

Sodium nitroprusside produces balanced arterial and venous vasodilation. It is rapidly converted to cyanide, which is detoxified using sulphur donors to thiocyanate; thiocyanate is cleared renally, creating distinct hepatic and renal toxicity considerations.

Formulation and product differences

• The selected product is a clear reddish-brown concentrate for intravenous infusion with water for injections as its only excipient.
• It requires dilution only with 5% glucose and must be protected from light.
• It must not be directly injected or mixed with additional medicines in the prepared infusion.

Solution for infusion

Route: Intravenous

Strengths: 50 mg/2 mL