Penicillin G (parenteral)

C. diff Risk


Oral Bioavailability


Approximate Cost



Renally cleared, requires dosage adjustment with changes in renal function. Consult a pharmacist for renal dosing.

100,000 to 250,000 units/kg/DAY divided q6h. Max 8 million units/DAY.

250,000 to 400,000 units/kg/DAY divided q4h. Max 24 million units/DAY.

General Information

Common Usage

Therapy of Streptococcal and other documented susceptible infections, syphilis

Drug Monitoring

Renal and hepatic function, CBC with differential, hypersensitivity reactions and IV site for phlebitis.

Adverse Effects

Allergy/rash (immediate or delayed), seizures, cytopenias, eosinophilia, interstitial nephritis, abnormal liver enzymes, serum sickness


Antimicrobial class: penicillin

Average serum half life: Neonates: <6 days: 3.2 to 3.4 hours. 7 to 13 days: 1.2 to 2.2 hours. >14 days: 0.9 to 1.9 hours.
Pediatrics: 0.5-1.2 hours.
Adults normal renal function: 30- 50 mintes

Route of Elimination: Renal (58% to 85% unchanged drug)