Medicines Management & Pharmacy Services (MMPS) LTHT Paediatric Critical Care Administration Guide Intravenous Sodium Phenylbutyrate Dose: Acute hyperammonaemia Confirm dose required with advising metabolic consultant Loading dose: 250mg/kg given over 90mins (this is not always required - please check) Continuous infusion: by 250mg/kg/day If necessary the dose may be increased to 500mg/kg/day (check with metabolic consultant if this is required) This is the metabolic consultants practice and doses are different than stated in the BNFc Route of Administer via a central or peripheral line. administration: Standard concentration of 50mg/mL For children weighing less than or equal to 20kg: 2.5gram in 50mL of glucose 5% or 10% For children weighing over 20kg to 40kg: 5gram in 100mL of glucose 5% or 10% For children weighing over 40kg: 12.5grams in 250mL of glucose 5% or 10% Note: 250mg/kg/day = 0.208mL/kg/hour Products available: Sodium Phenylbutyrate Injection 1g/5mL (200mg/mL) or 2g/10mL (200mg/mL) To prepare an Preferred diluent: Glucose 10% infusion: 2.5gram in 50mL; Draw up 12.5mL of sodium phenylbutyrate 200mg/mL(2.5gram) into a 50mL syringe and make up to 50mL with diluent (50mg/mL) 5gram in 100mL; Withdraw 25mL from the 100mL bag of diluent and discard. Draw up 25mL of sodium phenylbutyrate 200mg/mL(5gram) and add to bag. Mix well. Final concentration 50mg/mL. 12.5gram in 250mL; Withdraw 62.5mL from the 250mL bag of diluent and discard. Draw up 62.5mL of sodium phenylbutyrate 200mg/mL (12.5gram) and add to bag. Mix well. Final concentration 50mg/mL. How to prescribe: Prescribe the continuous infusion on an LTH Critical Care Intravenous Infusion Prescription Sheet. Compatibilities: Compatible at Y-site with sodium benzoate, carnitine and arginine Notes: If there is no compatibility information for specific drugs, do not assume compatibility, use a separate line. Aim is to maintain plasma concentration of ammonia below 60micromol/L and glutamine below 800micromol/L There is also a drug calculator on the bimdg website. For details visit www.bimdg.org.uk. This calculator will use a different method of making up the infusion than above. If using this site please check calculations independently and stability of formulation. References: Trissel, SPC, Medusa, BNFc online (accessed 16/08/21), Evelina Paediatric Formulary (accessed 16/08/21), BMIDG.org.uk (accessed 16/08/21) Provenance Date Produced: May 2013 Reviewed: August 2021 Valid until: August 2023 Author: Teresa Brooks, paediatric cardiology pharmacist Quality Assurance Check by: Jenny Jackson, paediatric pharmacist Produced by Clinical Pharmacy Services For further information contact [email protected] ext 65377 This information has been prepared by Leeds Medicines Management and Pharmacy Services for use by health care professionals at Leeds Teaching Hospitals NHS Trust .