Introduction

Name

• Penicillin G.

Class of drug

• Penicillin antibiotic.

Description

Chemical name

• [2S-(2-alpha,5-alpha,6-beta)]-3,3-dimethyl-7-oxo-6-[(phenylacetyl)amino]-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid.

Molecular formula

• C16H18N2O4S.

Physical properties

• Sterile powder.
• Sterile, aqueous suspension.

Storage requirements

• Powder:
  • <25°C.
• Suspension:
  • Between 2-8°C.
  • Do not store in freezer.
  • Protect from light.

Uses

Indications

• Used parenterally to treat serious infections caused by sensitive organisms, eg Streptococcus spp Streptococcus spp , Clostridium spp Clostridia spp , Borrelia borgderferi Borrelia burgdorferi , some Staphylococcus spp and fusospirochetes.
• When used for 'blind' therapy of undiagnosed serious infections penicillins may be given in conjunction with gentamicin Gentamicin and/or metronidazole Metronidazole.

Administration

Precautions

Interactions

with other drugs

Probenecid

• Blocks the renal tubular excretion of penicillins, producing higher and more prolonged plasma concentrations.

Aminoglycosides, eg gentamicin

• May inactivate penicillins when mixed together in parenteral solutions Gentamicin.

Streptomycin

• Synergistic action. However, as their pharmacokinetics differ, the use of such compound preparations is generally thought to be unjustified Streptomycin.

Adverse Reactions

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.

Other sources of information

• Plumb D C (2011) Plumb’s Veterinary Drug Handbook. 7th edn. Wiley-Blackwell, Ames, Iowa. 
• Based on Small Animal Formulary. Tennant, Bryn (1999) 3rd edn. Cheltenham: BSAVA.