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Penicillin G Potassium
Overview
Active ingredients
Source: NDC DirectoryForms, strengths and routes
Source: NDC DirectoryPharmacologic classes are listed in the class section below.
Pharmacologic class
Source: NDC Directory| Class | Type | Browse |
|---|---|---|
| Penicillin-class Antibacterial [EPC] | EPC | All 38 members |
| Penicillins [CS] | CS | All 38 members |
Regulatory status
Source: Drugs@FDANDC Directory| Product | Trade name | Form | Strength | Ingredient | Status | TE | Flags |
|---|---|---|---|---|---|---|---|
| 065448-001 | PENICILLIN G POTASSIUM | INJECTABLE | PENICILLIN G POTASSIUM | Prescription | AP | ||
| 065448-002 | PENICILLIN G POTASSIUM | INJECTABLE | PENICILLIN G POTASSIUM | Prescription | AP |
Therapeutic equivalence
Source: Orange BookWhat this rating means: Therapeutically equivalent — bioequivalence demonstrated (parenteral aqueous solutions)
Codes beginning with “A” indicate products the FDA considers therapeutically equivalent. Codes beginning with “B” indicate bioequivalence has not been established. See methodology.
Approval history
Source: Drugs@FDA| Type | No. | Action | Status | Date | Review |
|---|---|---|---|---|---|
| Supplement | 5 | Labeling | Approved | January 30, 2016 | Standard |
| Supplement | 3 | Labeling | Approved | August 24, 2012 | — |
| Original application | 1 | Approved | August 18, 2009 | — |
Prescribing information
Source: openFDA Drug LabelingReproduced verbatim from the Structured Product Labeling submitted to the FDA (effective 20250201). This is the manufacturer's labelling text, not a summary and not advice.
Indications and Usage
openFDA Drug LabelingINDICATIONS AND USAGE Therapy Buffered penicillin G potassium for injection 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 Buffered penicillin G potassium for injection 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 beta-hemolytic streptococcus ), other beta-hemolytic streptococci including groups C, H, G, L and M, Streptococcus pneumoniae and Staphylococcus species (non-penicillinase producing strains) Anthrax Bacillus anthracis Actinomycosis (cervicofacial disease and thoracic and abdominal disease) Actinomyces Israelil 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 rhusiopthiae 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) Escherichia coli, Enterobacter aerogenes, Alcaligenes faecalis, salmonella, shigella and Proteus mirabilis, Penicillin G is not the drug of choice in the treatment of gram-negative bacillary infections. To reduce the development of drug-resistant bacteria and maintain the 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.
Dosage and Administration
openFDA Drug LabelingDOSAGE AND ADMINISTRATION Buffered penicillin G potassium for injection may be given intravenously or intramuscularly. The usual dose recommendations are as follows: CLINICAL INDICATION DOSAGE Serious infections due to susceptible strains of streptococci (including S. pneumoniae) and staphylococci-septicemia , empyema, pneumonia, pericarditis, endocarditis and meningitis 5 to 24 million units/day depending on the infection and its severity administered in equally divided doses every 4 to 6 hours Anthrax Minimum of 8 million units/day in divided doses every 6 hours. Higher doses may be required depending on susceptibility of organism. Actinomycosis Cervicofacial disease 1 to 6 million units/day Thoracic and abdominal disease 10 to 20 million units/day Clostridial infections Botulism (adjunctive therapy to antitoxin) 20 million units/day Gas gangrene (debridement and/or surgery as indicated) Tetanus (adjunctive therapy to human tetanus immune globulin) Diphtheria (adjunctive therapy to antitoxin and for the prevention of the carrier state) 2 to 3 million units/day in divided doses for 10 to 12 days Erysipelothrix endocarditis 12 to 20 million units/day for 4 to 6 weeks Fusospirochetosis (severe infections of the oropharnyx [Vincent’s], lower respiratory tract and genital area) 5 to 10 million units/day Listeria infections Meningitis 15 to 20 million units/day for 2 weeks Endocarditis 15 to 20 million units/day for 4 weeks Pasteurella infections including bacteremia and meningitis 4 to 6 million units/day for 2 weeks Haverhill fever, Rat-bite fever 12 to 20 million units/day for 3 to 4 weeks Disseminated gonococcal infections, such as meningitis endocarditis, arthritis, etc., caused by penicillin-susceptible organisms 10 million units/day; duration depends on the type of infection Syphilis (neurosyphilis) 12 to 24 million units/day, as 2 to 4 MU every 4 hours for 10 to 14 days; many experts recommend additional therapy with Benzathine PCN G 2.4 MU intramuscular weekly for 3 doses after completion of intravenous therapy Meningococcal meningitis and/or septicemia 24 million units/day as 2 million units every 2 hours * Because of its short half-life, penicillin G is administered in divided doses, usually every 4 to 6 hours with the exception of meningococcal meningitis/septicemia, i.e., every 2 hours. Pediatric patients This product should not be administered to patients requiring less than one million units per dose (see PRECAUTIONS – Pediatric Use ). CLINICAL INDICATION DOSAGE Serious infections, such as pneumonia and endocarditis, due to susceptible strains of streptococci (including S. pneumoniae) and meningococcus 150,000 units/kg/day divided in equal doses every 4 to 6 hours; duration depends on infecting organism and type of infection. Meningitis caused by susceptible strains of pneumococcus and meningococcus 250,000 units/kg/day divided in equal doses every 4 hours for 7 to 14 days depending on the infecting organism (maximum dose of 12 to 20 million units/day) Disseminated Gonococcal infections (penicillin-susceptible strains) weight less than 45 kg: Arthritis 100,000 units/kg/day in 4 equally divided doses for 7 to 10 days Meningitis 250,000 units/kg/day in equal doses every 4 hours for 10 to 14 days Endocarditis 250,000 units/kg/day in equal doses every 4 hours for 4 weeks Arthritis, meningitis, endocarditis weight 45 kg or greater: 10 million units/day in 4 equally divided doses with the duration of therapy depending on the type of infection Syphilis (congenital and neurosyphilis) after the newborn period 200,000 to 300,000 units/kg/day (administered as 50,000 units/kg every 4 to 6 hours) for 10 to 14 days Diphtheria (adjunctive therapy to antitoxin and for prevention of the carrier state) 150,000 to 250,000 units/kg/day in equal doses every 6 hours for 7 to 10 days Rat-bite fever; Haverhill fever (with endocarditis caused by S. moniliformis) 150,000 to 250,000 units/kg/day in equal doses every 4 hours for 4 weeks Renal …
Contraindications
openFDA Drug LabelingCONTRAINDICATIONS A history of a hypersensitivity (anaphylactic) reaction to any penicillin is a contraindication.
Warnings
openFDA Drug LabelingWARNINGS Anaphylaxis Serious and occasionally fatal hypersensitivity (anaphylactic) reactions have been reported in patients on penicillin therapy. These reactions are more likely to occur in individuals with a history of penicillin hypersensitivity and/or a history of sensitivity to multiple allergens. There have been reports of individuals with a history of penicillin hypersensitivity who have experienced severe reactions when treated with cephalosporins. Before initiating therapy with penicillin G, careful inquiry should be made concerning previous hypersensitivity reactions to penicillins, cephalosporins, or other allergens. If an allergic reaction occurs, penicillin G should be discontinued and appropriate therapy instituted. Severe cutaneous adverse reactions Severe cutaneous adverse reactions (SCAR), such as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) have been reported in patients taking beta-lactam antibiotics. When SCAR is suspected, Penicillin G Potassium for Injection should be discontinued immediately and an alternative treatment should be considered. Clostridioides difficile associated diarrhea Clostridioides difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including Penicillin G Potassium for Injection and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile . C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile , and surgical evaluation should be instituted as clinically indicated.
Adverse Reactions
openFDA Drug LabelingADVERSE 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, ranging from maculopapular eruptions to exfoliative dermatitis. Contact dermatitis has been observed in individuals who prepare penicillin solutions. Gastrointestinal system Pseudomembranous colitis has been reported with the onset occurring during or after penicillin G treatment. Nausea, vomiting, stomatitis, black or hairy tongue, and other symptoms of gastrointestinal irritation may occur, especially during oral therapy. Hematologic system Reactions include neutropenia, which resolves after penicillin therapy is discontinued; Coombs-positive hemolytic anemia, an uncommon reaction, occurs in patients treated with intravenous penicillin G in doses greater than 10 million units/day and who have previously received large doses of the drug; and with large doses of penicillin, a bleeding diathesis can occur secondary to platelet dysfunction. Metabolic Penicillin G Potassium for Injection (1 million units contains 1.68 mEq of potassium ion) may cause serious and even fatal electrolyte disturbances, i.e., hyperkalemia, when given intravenously in large doses. Nervous system Neurotoxic reactions including hyperreflexia, myoclonic twitches, seizures and coma have been reported following the administration of massive intravenous doses and are more likely in patients with impaired renal function. Urogenital system Renal tubular damage and interstitial nephritis have been associated with large intravenous doses of penicillin G. Manifestations of this reaction may include fever, rash, eosinophilia, proteinuria, eosinophiluria, hematuria and a rise in serum urea nitrogen. Discontinuation of penicillin G results in resolution in the majority of patients. Local reactions Phlebitis and thrombophlebitis may occur, and pain at the injection site has been reported with intravenous administration. Immune system disorders Acute myocardial ischemia with or without myocardial infarction may occur as part of an allergic reaction. To report SUSPECTED ADVERSE REACTIONS …
Drug Interactions
openFDA Drug LabelingDrug 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.
Description
openFDA Drug LabelingDESCRIPTION Penicillin G Potassium, USP is a natural penicillin. It is chemically designated 4-Thia-1-azabicyclo [3.2.0]heptane-2-carboxylic acid,3,3-dimethyl-7-oxo-6-[(phenylacetyl)amino]-, monopotassium salt, [2 S -(2α, 5α, 6β)]. Penicillin G potassium is a colorless or white crystal, or a white crystalline powder which is odorless, or practically so, and moderately hygroscopic. It is freely soluble in water, in isotonic sodium chloride solution and in dextrose solution. The structural formula is as shown below. C 16 H 17 KN 2 O 4 S M.W. 372.48 Buffered Penicillin G Potassium for Injection, USP is a sterile, pyrogen-free powder for reconstitution. Buffered Penicillin G Potassium for Injection, USP is an antibacterial agent for intramuscular, continuous intravenous drip, intrapleural or other local infusion, and intrathecal administration. Penicillin G Potassium for Injection, USP is supplied in vials equivalent to 5,000,000 units (5 million units) or 20,000,000 units (20 million units) of penicillin G as the potassium salt. Each million units contains approximately 6.8 milligrams of sodium (0.3 mEq) and 65.6 milligrams of potassium (1.68 mEq). Buffered with sodium citrate to a pH of 6.0 to 8.5. Structural Formula
Overdosage
openFDA Drug LabelingOVERDOSAGE 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.
How Supplied / Storage and Handling
openFDA Drug LabelingHOW SUPPLIED Penicillin G Potassium for Injection, USP is supplied in dry powder form in vials containing 1,000,000 units (1 million units), 5,000,000 units (5 million units) or 20,000,000 units (20 million units) of crystalline penicillin G as the potassium salt, buffered with sodium citrate to an optimum pH. Each million units contains approximately 6.9 milligrams of sodium (0.3 mEq) and 65.8 milligrams of potassium (1.68 mEq). NDC Penicillin G Potassium for Injection, USP Package Factor 72603-210-10 5,000,000 units per vial 10 vials per carton 72603-345-01 20,000,000 units per vial 1 vial per carton Storage Conditions Store dry powder at 20°C to 25°C (68°F to 77°F) [see USP Controlled Room Temperature]. Sterile constituted solutions may be kept in a refrigerator at 2o to 8oC (36o to 46oF). When refrigerated, penicillin solutions may be stored for seven days without loss of potency. DISCARD UNUSED SOLUTION AFTER 7 DAYS. Sterile, Nonpyrogenic, Preservative-free. This container closure is not made with natural rubber latex. The brand names mentioned in this document are the trademarks of their respective owners. Manufactured for: Northstar Rx LLC, Memphis, TN 38141. Toll-free: 1-800-206-7821 Manufactured by: Istituto Biochimico Italiano Giovanni Lorenzini S.p.A. Via Fossignano 2, 04011 Aprilia (LT), Italy Issued November 2023
Adverse event reports
Source: openFDA FAERSAttributed to this product's most-reported active ingredient: PENICILLIN G POTASSIUM. Combination products with more than six active ingredients are not attributed, because a report count summed across a long ingredient list measures the list, not the medicine.
Recalls
Source: FDA Enforcement| Classification | Reported | Firm | Reason | Status |
|---|---|---|---|---|
| Class I | July 9, 2025 | Sandoz Inc | Labeling: Label Mix-Up; Some vials of Cefazolin for Injection, USP 1 gram were incorrectly labeled as penicillin G potassium for Injection, USP, 20 million Unit | Ongoing |
Packaging and NDCs
Source: NDC Directory| Package NDC | Product NDC | Labeler | Description | Marketing start |
|---|---|---|---|---|
| 70860-127-51 | 70860-127 | Athenex Pharmaceutical Division, LLC. | 1 VIAL in 1 CARTON (70860-127-51) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | May 21, 2019 |
| 83634-102-20 | 83634-102 | Avenacy Inc. | 10 VIAL in 1 CARTON (83634-102-20) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL (83634-102-41) | February 1, 2025 |
| 83634-103-51 | 83634-103 | Avenacy Inc. | 1 VIAL in 1 CARTON (83634-103-51) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | February 1, 2025 |
| 51662-1689-1 | 51662-1689 | HF Acquisition Co LLC, DBA HealthFirst | 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL (51662-1689-1) | March 1, 2024 |
| 51662-1709-1 | 51662-1709 | HF Acquisition Co LLC, DBA HealthFirst | 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL (51662-1709-1) | December 1, 2024 |
| 72603-210-01 | 72603-210 | NorthStar Rx, LLC | 1 VIAL in 1 CARTON (72603-210-01) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | March 1, 2024 |
| 72603-210-10 | 72603-210 | NorthStar Rx, LLC | 10 VIAL in 1 CARTON (72603-210-10) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | March 1, 2024 |
| 72603-345-01 | 72603-345 | NorthStar Rx, LLC | 1 VIAL in 1 CARTON (72603-345-01) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | March 1, 2024 |
| 25021-153-20 | 25021-153 | Sagent Pharmaceuticals | 10 VIAL in 1 CARTON (25021-153-20) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | December 1, 2024 |
| 25021-154-51 | 25021-154 | Sagent Pharmaceuticals | 1 VIAL in 1 CARTON (25021-154-51) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | November 1, 2024 |
| 0781-6135-95 | 0781-6135 | Sandoz Inc | 10 VIAL in 1 CARTON (0781-6135-95) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL (0781-6135-94) | August 30, 2001 |
| 0781-6136-94 | 0781-6136 | Sandoz Inc | 1 VIAL in 1 CARTON (0781-6136-94) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | August 30, 2001 |
| 44567-310-10 | 44567-310 | WG Critical Care, LLC | 10 VIAL in 1 TRAY (44567-310-10) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | May 10, 2012 |
| 44567-311-10 | 44567-311 | WG Critical Care, LLC | 10 VIAL in 1 TRAY (44567-311-10) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | May 10, 2012 |
| 44567-312-01 | 44567-312 | WG Critical Care, LLC | 1 VIAL in 1 CARTON (44567-312-01) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | May 10, 2012 |
| 44567-312-10 | 44567-312 | WG Critical Care, LLC | 10 VIAL in 1 CARTON (44567-312-10) / 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | May 10, 2012 |
| 70860-127 | 70860-127 | Athenex Pharmaceutical Division, LLC. | — | May 21, 2019 |
| 83634-102 | 83634-102 | Avenacy Inc. | — | February 1, 2025 |
| 83634-103 | 83634-103 | Avenacy Inc. | — | February 1, 2025 |
| 51662-1689 | 51662-1689 | HF Acquisition Co LLC, DBA HealthFirst | — | March 1, 2024 |
| 51662-1709 | 51662-1709 | HF Acquisition Co LLC, DBA HealthFirst | — | December 1, 2024 |
| 72603-210 | 72603-210 | NorthStar Rx, LLC | — | March 1, 2024 |
| 72603-345 | 72603-345 | NorthStar Rx, LLC | — | March 1, 2024 |
| 25021-153 | 25021-153 | Sagent Pharmaceuticals | — | December 1, 2024 |
| 25021-154 | 25021-154 | Sagent Pharmaceuticals | — | November 1, 2024 |
| 0781-6135 | 0781-6135 | Sandoz Inc | — | August 30, 2001 |
| 0781-6136 | 0781-6136 | Sandoz Inc | — | August 30, 2001 |
| 44567-310 | 44567-310 | WG Critical Care, LLC | — | May 10, 2012 |
| 44567-311 | 44567-311 | WG Critical Care, LLC | — | May 10, 2012 |
| 44567-312 | 44567-312 | WG Critical Care, LLC | — | May 10, 2012 |
Sources for this page
| Dataset | Agency | Used for |
|---|---|---|
| NDC Directory | FDA | Identity, ingredients, strengths, forms, routes, labelers, packages |
| Drugs@FDA | FDA | Application, sponsor, submissions, review documents, marketing status |
| Orange Book | FDA | Therapeutic equivalence codes, reference drug flags, patents, exclusivity |
| Drug Labeling | FDA / NLM | Prescribing information reproduced above |
| FAERS | FDA | Adverse event report counts |
| Enforcement | FDA | Recall records |
Generated September 25, 2026 · 13 sections on this page.