Brand Names

PENICILLIN
PENICILLIN G POTASSIUM
PENICILLIN G POTASSIUM IN PLASTIC CONTAINER
PENICILLIN-2
PENTIDS ‘200’
PENTIDS ‘250’
PENTIDS ‘400’
PENTIDS ‘800’
PFIZERPEN
PFIZERPEN G

Potassium

Indications and Usage

Therapy: 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. Clinical Indication Infecting Organism 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) Anthrax 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 Meni

Dosage and Administration

Penicillin G Potassium for Injection, USP may be given intravenously or intramuscularly. The usual dose recommendations are as follows:

Contraindications

A history of a hypersensitivity (anaphylactic) reaction to any penicillin is a contraindication.

Adverse Reactions

Body As A Whole The Jarisch-Herxheimer reaction is a systemic reaction, that may occur after the initiation of penicillin therapy in patients with syphilis or other spirochetal infections (i.e., Lyme disease and Relapsing fever). The reaction begins one or two hours after initiation of therapy and disappears within 12 to 24 hours. It is characterized by fever, chills, myalgias, headache, exacerbation of cutaneous lesions, tachycardia, hyperventilation, vasodilation with flushing and mild hypotension. The pathogenesis of the Herxheimer reaction may be due to the release from the spirochetes of heat-stable pyrogen. Hypersensitivity Reactions The reported incidence of allergic reactions to all penicillins ranges from 0.7 to 10 percent in different studies (see WARNINGS ). Sensitization is usually the result of previous treatment with a penicillin, but some individuals have had immediate reactions when first treated. In such cases, it is postulated that prior exposure to penicillin may have occurred via trace amounts present in milk or vaccines. Two types of allergic reactions to penicillin are noted clinically – immediate and delayed. Immediate reactions usually occur within 20 minutes of administration and range in severity from urticaria and pruritus to angioneurotic edema, laryngospasm, bronchospasm, hypotension, vascular collapse and death (see WARNINGS). Such immediate anaphylactic reactions are very rare and usually occur after parenteral therapy, but a few cases of anaphylaxis have been reported following oral therapy. Another type of immediate reaction, an accelerated reaction, may occur between 20 minutes and 48 hours after administration and may include urticaria, pruritus, fever and, occasionally, laryngeal edema. Delayed reactions to penicillin therapy usually occur within 1 to 2 weeks after initiation of therapy. Manifestations include serum sickness-like symptoms, i.e., fever, malaise, urticaria, myalgia, arthralgia, abdominal pain and various skin rashes

Drug Interactions

Bacteriostatic antibacterials (i.e., chloramphenicol, erythromycins, sulfonamides or tetracyclines) may antagonize the bactericidal effect of penicillin, and concurrent use of these drugs should be avoided. This has been documented in vitro; however, the clinical significance of this interaction is not well-documented. Penicillin blood levels may be prolonged by concurrent administration of probenecid which blocks the renal tubular secretion of penicillins. Other drugs may compete with penicillin G for renal tubular secretion and thus prolong the serum half-life of penicillin. These drugs include: aspirin, phenylbutazone, sulfonamides, indomethacin, thiazide diuretics, furosemide and ethacrynic acid.

Overdosage

Dose related toxicity may arise with the use of massive doses of intravenous penicillins (40 to 100 million units per day), particularly in patients with severe renal impairment (see PRECAUTIONS ). The manifestations may include agitation, confusion, asterixis, hallucinations, stupor, coma, multifocal myoclonus, seizures and encephalopathy. Hyperkalemia is also possible (see ADVERSE REACTIONS, Metabolic ). In case of overdosage, discontinue penicillin, treat symptomatically and institute supportive measures as required. If necessary, hemodialysis may be used to reduce blood levels of penicillin G, although the degree of effectiveness of this procedure is questionable.

⚠ Caution

Medical Disclaimer: This information is for educational purposes only. Always consult a healthcare professional before taking any medication.