Medical Information
United States

In order to provide you with relevant and meaningful content we need to know more about you.

Please choose the category that best describes you.

This content is intended for U.S. Healthcare Professionals. Would you like to proceed?

If you provide additional keywords, you may be able to browse through our database of Scientific Response Documents.

Our scientific content is evidence-based, scientifically balanced and non-promotional. It undergoes rigorous internal medical review and is updated regularly to reflect new information.

PFIZERPEN® Indications and Usage (penicillin G potassium)



Penicillin G Potassium for Injection, USP is indicated in the treatment of serious infections caused by susceptible strains of the designated microorganisms in the conditions listed below.

Appropriate culture and susceptibility tests should be done before treatment in order to isolate and identify organisms causing infection and to determine their susceptibility to penicillin G.

Therapy with Penicillin G Potassium for Injection, USP may be initiated before results of such tests are known when there is reason to believe the infection may involve any of the organisms listed below; however, once these results become available, appropriate therapy should be continued.


Septicemia, empyema, pneumonia, pericarditis, endocarditis, meningitis

Streptococcus pyogenes (group A β-hemolytic streptococcus), other β-hemolytic streptococci including groups C, H, G, L and M, Streptococcus pneumoniae and Staphylococcus species (non-penicillinase producing strains)


Bacillus anthracis

Actinomycosis (cervico-facial disease and thoracic and abdominal disease)

Actinomyces israelii

Botulism (adjunctive therapy to antitoxin), gas gangrene, and tetanus (adjunctive therapy to human tetanus immune globulin)

Clostridium species

Diphtheria (adjunctive therapy to antitoxin and prevention of the carrier state)

Corynebacterium diphtheriae

Erysipelothrix endocarditis

Erysipelothrix rhusiopathiae

Fusospirochetosis (severe infections of the oropharynx [Vincent's], lower respiratory tract and genital area)

Fusobacterium species and spirochetes

Listeria infections including meningitis and endocarditis

Listeria monocytogenes

Pasteurella infections including bacteremia and meningitis

Pasteurella multocida

Haverhill fever

Streptobacillus moniliformis

Rat bite fever

Spirillum minus or Streptobacillus moniliformis

Disseminated gonococcal infections

Neisseria gonorrhoeae (Penicillin-susceptible)

Syphilis (congenital and neurosyphilis)

Treponema pallidum

Meningococcal meningitis and/or septicemia

Neisseria meningitidis

Gram-negative bacillary infections (bacteremias)
Penicillin G is not the drug of choice in the treatment of Gram-negative bacillary infections.

Gram-negative bacillary organisms (i.e. Enterobacteriaceae)

To reduce the development of drug-resistant bacteria and maintain effectiveness of Penicillin G Potassium and other antibacterial drugs, Penicillin G Potassium should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

Did you find an answer to your question? Yes No
Didn’t find what you were looking for? Contact us.
Report Adverse Event