Parenteral Manual


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Alternate Name(s): 
Sodium Benzoate/Sodium Phenylacetate
Urea cycle disorder treatment agent
Original Date: 
August 2005
Revised Date: 
September 2011
  • Acute treatment of hyperammonemia associated with urea cycle disorders
Reconstitution and Stability: 
  • Store at room temperature
  • Available as a 10% solution which equals:
    - 100 mg/mL sodium phenylacetate
    - 100 mg/mL sodium benzoate
  • Must be diluted before administration
  • Filter through a Millex-GV mm sterile filter 0.22 micron while injecting drug into D10W minibag
  • Solutions with sodium bicarbonate are stable 24 hours at room temperature
  • Solutions with D10W and/or arginine stable 24 hours

- Solutions Compatible: D10W ONLY

- Additive/Above Cassette Compatible: arginine HCl, sodium bicarbonate

- Y-site Compatibility: arginine HCL, sodium bicarbonate


(For approved routes of administration by nursing personnel, refer to Policy for the Administration of Intravenous Medications.)

IV Direct


IV Intermittent Infusion YES; central line preferred
Usual dilution: 10 mg/mL
Infusion time: 90 minutes
IV Continuous Infusion YES; central line preferred
Usual dilution: 10 mg/mL

(For neonatal dosages, refer to Neonatal IV Drug Manual.)

  • Loading: 250 mg/kg/dose IV as a loading dose. Give IV over 90 minutes
  • Maintenance: Followed by 250 mg/kg/day as a continuous IV infusion
  • Loading: 5.5 g/m2/dose IV as a loading dose. Give IV over 90 minutes
  • Maintenance: Followed by 5.5 g/m2/day as a continuous IV infusion


Potential hazards of parenteral administration: 
  • IV infiltration may cause necrosis and phlebitis
  • Nausea, vomiting (especially with loading dose)
  • Metabolic acidosis, hyperglycemia, hypokalemia, hypocalcemia, hyperammonemia, hypernatremia
  • Convulsions, mental impairment
  • Monitor plasma ammonia levels, neurological status, blood pH and pCO2
  • Use caution in patients with renal or hepatic insufficiency
  • Caution in neonates: displaces bilirubin from protein-binding sites
  • Administration of analogous oral drugs (Buphenyl), should be stopped prior to sodium phenylacetate/sodium benzoate infusion.
  • Ammonul® 100 mg/mL contains 0.52 mmol of sodium/mL
  • Available in metabolic kit in resus room in emergency

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