Neonatal Drug Therapy Manual

Penicillin G, Sodium

Disclaimer: Official controlled document is the CHEO and Ottawa Hospital online copy. It is the responsibility of user to ensure that any paper copy version is the same as the online version before use.

Original Date: 
March 1993
Revised Date: 
March 2022
  • Infections due to Gram (+), some Gram (-) and anaerobic organisms
  • IV intermittent infusion: over 15 - 30 minutes




Congenital Syphilis

Group B Streptococcal Meningitis

1 wk: < 2 kg


          > 2 kg

100 000 U/kg/day divided Q12h


150 000 U/kg/day divided q8h


Regardless of weight:

100 000 U/kg/day divided Q12h

Regardless of weight:

250 000-450 000 U/kg/day divided Q8h

>1 wk: <1.2 kg

            1.2 kg - 2 kg

            > 2 kg

100 000 U/kg/day divided Q12h

150 000 U/kg/day divided Q8h

200 000 U/kg/day divided Q6h

Regardless of weight:

150 000 U/kg/day divided Q8h

Regardless of weight:

500 000 U/kg/day divided Q4-6h

Side Effects: 
  • CNS: lethargy, seizures (with high doses and renal impairment)
  • Endocrine and metabolic: electrolyte imbalances
  • Hematologic: neutropenia, leukopenia, hemolytic anemia, thrombocytopenia (with high doses)
  • Local: thrombophlebitis
  • Renal: acute interstitial nephritis (rare, with prolonged therapy)
Parameters to Monitor: 
  • CBC, platelets (with high doses)
  • Temperature
  • Renal function tests
  • Serum electrolytes
Reconstitution and Stability: 

IV intermittent Infusion:

Ensure to double check the concentratiuon of the vial before mixing

  • Using Penicillin G Sodium 1 million units (MU) vial
    • Add 1.8 mL SWFI to vial 
    • Withdraw contents of vial (1 MU) and dilute to a total of 10 mL with D5W or 0.9% NaCl.
    • Final concentration: 100 000 units/mL


  • Using Penicillin G Sodium 5 million units (MU) vial
    • Add 8.2 mL SWFI to vial
    • Take 4 mL (2 MU) and add to 16 mL D5W or 0.9% NaCl
    • Final concentration: 100 000 units/mL

- Solution Compatible: D5W, 0.9% NaCl

- Y-site Compatible: calcium gluconate, dopamine, furosemide, gentamicin, KCl, ranitidine, SMOF, TPN


1 million units of penicillin G sodium contains 2 mmol Na.


-Taketomo CK, Hodding JH, Kraus DM. Pediatric Dosage Handbook 22nd Edition. Hudson: Lexi-Comp Inc.; 2015

-American Society on Health-System Pharmacists (ASHP).  Handbook on Injectable Drugs. 19th Edition. Bethesda: American Society of Health-System Pharmacists; 2017

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