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Pfizerpen penicillin G potassium 5000000 [iU]/1 Powder, For Solution, 10 vials
Other active recalls for Penicillin G Potassium (different manufacturers) — 1 · tap to view
🆔 Identity & classification
Where does this data come from?
🏷️ RxNorm drug class
This medicine belongs to the Penicillin-class Antibacterial class.
Where does this data come from?
🏭 Manufacturer & labeler
Where does this data come from?
🩺 Clinical
Penicillin G injection is used to treat and prevent certain infections caused by bacteria. Penicillin G injection is in a class of medications called penicillins. It works by killing bacteria that cause infections. Antibiotics such as penicillin G injection will not work for colds, flu, or other viral infections. Taking antibiotics when they are not needed increases your risk of getting an infection later that resists antibiotic treatment.
Read the full MedlinePlus article ↗- Penicillin G injection is reserved for serious, potentially life-threatening infections where we need high levels of antibiotic in your blood fast. An IV or intramuscular injection...
- Why am I getting this antibiotic through an IV instead of just taking a pill?
- Prior exposure without a reaction is reassuring, but it doesn't completely rule out a future allergic reaction. Allergies can develop over time or after repeated exposures. The mor...
- I've taken penicillin before without a problem. Do I still need to worry about an allergic reaction?
Patient education
Supplement & herbal interactions
Some supplements/herbs that may interact with Penicillin G Potassium — tap one for details:
Penicillin G Potassium may be associated with lower levels of 7 nutrients — worth a chat with your pharmacist, not a cause for alarm.
Where does this data come from?
Ask a licensed pharmacist directly — free, answered by our team.
🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.
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UNII 2968PHW8QP
A weak organic acid derived from citrus fruits or made through fermentation. It works as a buffer to control pH, a preservative to extend shelf life, and a flavoring agent in medications.
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UNII 1Q73Q2JULR
Sodium citrate is a salt derived from citric acid. It works as a buffer to maintain the medicine's pH level and may also help improve taste or act as a preservative in the formulation.
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UNII P1BM4ZH95L
A salt derived from phosphoric acid, sodium polymetaphosphate acts as a sequestrant and buffering agent in medicines. It helps maintain stability and control acidity in liquid formulations.
3 inactive ingredients listed in the exact product block matched to this NDC.
Where does this data come from?
ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.Inactive ingredient FAQ
Are inactive ingredients the same for every manufacturer?
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Can inactive ingredients matter?
💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per mL | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | Not in the retail survey — common for institutional, discontinued, or low-volume packs. | |
| Medicaid paysCMS SDUD · 12 mo | No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data. | |
| Medicare drug plans payPart D · quarterly | No Part D plan price is available for this NDC in our data. | |
| Medicare Part B allowsASP · J2540 | $0.637 / J2540 unit | — |
Where does this data come from?
🧾 Billing & reimbursement
Where does this data come from?
🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Pfizerpen 5000000 [iU] 00049-0420-10 | Roerig | 10 vials | — | AP | FDA listed | — |
| Pfizerpen 20000000 [iU] 00049-0430-20 | Roerig | 1 vial | — | AP | FDA listed | — |
| Pfizerpen 5000000 [iU]this 00049-0520-22 | Roerig | 10 vials | — | AP | FDA listed | — |
| Pfizerpen 20000000 [iU] 00049-0530-22 | Roerig | 1 vial | — | AP | FDA listed | — |
| Penicillin G Potassium 5000000 [iU] 00781-6135-95 | Sandoz | 10 vials | — | — | FDA listed | — |
| Penicillin G Potassium 20000000 [iU] 00781-6136-94 | Sandoz | 1 vial | — | — | FDA listed | — |
| Penicillin G Potassium 5000000 [iU] 25021-0153-20 | Sagent | 10 vials | — | AP | FDA listed | — |
| Penicillin G Potassium 20000000 [iU] 25021-0154-51 | Sagent | 1 vial | — | AP | FDA listed | — |
| Penicillin G Potassium 1000000 [iU] 44567-0310-10 | WG | 10 vials | — | — | FDA listed | — |
| Penicillin G Potassium 5000000 [iU] 44567-0311-10 | WG | 10 vials | — | AP | FDA listed | — |
| Penicillin G Potassium 20000000 [iU] 44567-0312-10 | WG | 10 vials | — | AP | FDA listed | — |
| Buffered Penicillin G Potassium 5000000 [iU] 51662-1436-01 | HF | 1 injection | — | — | Discontinued | — |
| Penicillin G Potassium 5000000 [iU] 51662-1689-01 | HF | 1 injection | — | AP | FDA listed | — |
| Penicillin G Potassium 20000000 [iU] 70860-0127-51 | Athenex | 1 vial | — | AP | FDA listed | — |
| Penicillin G Potassium 5000000 [iU] 72603-0210-01 | NorthStar | 1 vial | — | AP | FDA listed | — |
| Penicillin G Potassium 20000000 [iU] 72603-0345-01 | NorthStar | 1 vial | — | AP | FDA listed | — |
| Penicillin G Potassium 5000000 [iU] 83634-0102-20 | Avenacy | 10 vials | — | AP | FDA listed | — |
| Penicillin G Potassium 20000000 [iU] 83634-0103-51 | Avenacy | 1 vial | — | AP | FDA listed | — |
Where does this data come from?
⏳ Availability & generic status
This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.
Where does this data come from?
💊 Medicaid utilization by pack size
📊 Medicare Part D spend CMS · PART D · 2026 (Q1)
🔬 Reported adverse events (FAERS)
Top reported reactions
Age at onset
Reporter sex
Where does this data come from?
📦 Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Status |
|---|---|---|---|
| 00049-0520-22 You're viewing this | 10 VIAL in 1 CARTON (0049-0520-22) / 1 POWDER, FOR SOLUTION in 1 VIAL | 2010-06-01 | Active |
| 00049-0520-83 | 10 VIAL in 1 CARTON (0049-0520-83) / 1 POWDER, FOR SOLUTION in 1 VIAL (0049-0520-84) | 2010-06-01 | Active |
This pack shows little to no recent Medicaid volume — a different pack size carries most fills. See all packs ↓
Pack size FAQ
What quantity is in NDC 00049-0520-22?
What is the difference between NDC 00049-0520-22 and NDC 00049-0520-83?
What NDC number is used to bill for this package of Pfizerpen penicillin G potassium 5000000 [iU]/1 Powder, For Solution?
🧭 About this NDC listing & data coverage
What data is (and isn’t) available for this NDC — tap to expand
| NDC identity (package / product / labeler codes) | ✓ Available |
| Labeler | ✓ Available |
| Product & package description | ✓ Available |
| Marketing category & status | ✓ Available |
| Active ingredient / dosage form / route | ✓ Available |
| FDA label (SPL via DailyMed) | ✓ Available |
| Package photos | ✓ Available |
| Inactive ingredients (structured) | ✓ Available |
| NADAC pharmacy acquisition price (CMS) | — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey. |
| Orange Book / therapeutic-equivalence data | ✓ Available |
| HCPCS J-code billing crosswalk | ✓ Available |
| Medicaid utilization (CMS SDUD) | — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold. |
Questions about this listing
Why is there no price listed?
Is the NDC printed on the package the same as the 11-digit billing NDC?
What do the three segments of this NDC mean?
Is this package still being marketed?
Does this product come in other package sizes?
Who lists this product with the FDA?
Do I need a prescription for this product?
Does this product have a billing J-code?
Where does this data come from?
📄 Full prescribing information FDA SPL
🎯 Indications and Usage ▾
INDICATIONS AND USAGE Therapy 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 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 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 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.
⏱️ Dosage and Administration ▾
DOSAGE AND ADMINISTRATION Buffered Penicillin G Potassium for Injection, USP may be given intravenously or intramuscularly. The usual dose recommendations are as follows: Adult patients CLINICAL INDICATION DOSAGE Serious infections due to susceptible strains of streptococci (including S. pneumoniae ) 12 to 24 million units/day depending on the infection and its severity administered in equally divided doses every 4–6 hours. -septicemia, empyema, pneumonia, pericarditis, endocarditis and meningitis Serious infections due to susceptible strains of staphylococci 5 to 24 million units/day depending on the infection and its severity administered in equally divided doses every 4–6 hours. -septicemia, empyema, pneumonia, pericarditis, endocarditis and meningitis 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( Because of its short half-life, Penicillin G is administered in divided doses, usually every 4–6 hours with the exception of meningococcal meningitis/septicemia, i.e ., every 2 hours. ) 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 10–12 days( ) Erysipelothrix endocarditis 12 to 20 million units/day for 4–6 weeks( ) Fusospirochetosis (severe infections of the oropharynx [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 3–4 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 2–4 MU every 4 hours for 10–14 days; many experts recommend additional therapy with Benzathine PCN G
2.4MU IM weekly for 3 doses after completion of IV therapy Meningococcal meningitis and/or septicemia 24 million units/day as 2 million units 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 150,000–300,000 units/kg/day divided in equal doses every 4–6 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 7–14 days depending on the infecting organism (maximum dose of 12–20 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 7–10 days Meningitis 250,000 units/kg/day in equal doses every 4 hours for 10–14 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 equally divided doses with the duration of therapy depending on the type of infection Syphilis (congenital and neurosyphilis) after the newborn period 200,000–300,000 units/kg/day (administered as 50,000 units/kg every 4–6 hours) for 10–14 days Diphtheria (adjunctive therapy to antitoxin and for prevention of the carrier…
⛔ Contraindications ▾
CONTRAINDICATIONS A history of a hypersensitivity (anaphylactic) reaction to any penicillin is a contraindication.
⚠️ Warnings ▾
WARNINGS 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 ▾
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 1–2 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 EVENTS, c…
🔄 Drug Interactions ▾
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.
🔄 Drug / Laboratory Test Interactions ▾
Drug/Laboratory Test Interactions After treatment with penicillin G, a false-positive reaction for glucose in the urine may occur with Benedict's solution, Fehling's solution or Clinitest ® tablet, but not with the enzyme-based tests, such as Clinistix ® and Tes-Tape ® . Penicillin G has been associated with pseudoproteinuria by certain test methods.
🤰 Pregnancy ▾
Pregnancy Teratogenic Effects Reproduction studies performed in the mouse, rat, and rabbit have revealed no evidence of impaired fertility or harm to the fetus due to penicillin G. Human experience with the penicillins during pregnancy has not shown any positive evidence of adverse effects on the fetus. There are, however, no adequate and well controlled studies in pregnant women showing conclusively that harmful effects of these drugs on the fetus can be excluded.
Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.
🧒 Pediatric Use ▾
Pediatric Use Incompletely developed renal function in newborns may delay elimination of penicillin; therefore, appropriate reductions in the dosage and frequency of administration should be made in these patients. All newborns treated with penicillins should be monitored closely for clinical and laboratory evidence of toxic or adverse effects (see Precautions ). Pediatric doses are generally determined on a weight basis and should be calculated for each patient individually.
Recommended guidelines for pediatric dosages are presented in Dosage and Administration .
🧓 Geriatric Use ▾
Geriatric Use Clinical studies of penicillin G injection did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
This drug is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function. Penicillin G Potassium for Injection contains 6.8 mg (0.3 mEq) of sodium per million units.
At the usual recommended doses of 10 to 20 million units per day patients would receive between 68 and 136 mg/day (3 and 6 mEq) of sodium per day. The geriatric population may respond with a blunted natriuresis to salt loading. This may be clinically important with regard to such diseases as congestive heart failure.
🆘 Overdosage ▾
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.
🧬 Clinical Pharmacology ▾
CLINICAL PHARMACOLOGY Aqueous penicillin G is rapidly absorbed following both intramuscular and subcutaneous injection. Initial blood levels following parenteral administration are high but transient. Penicillins bind to serum proteins, mainly albumin.
Therapeutic levels of the penicillins are easily achieved under normal circumstances in extracellular fluid and most other body tissues. Penicillins are distributed in varying degrees into pleural, pericardial, peritoneal, ascitic, synovial, and interstitial fluids. Penicillins are excreted in breast milk.
Penetration into the cerebrospinal fluid, eyes, and prostate is poor. Penicillins are rapidly excreted in the urine by glomerular filtration and active tubular secretion, primarily as unchanged drug. Approximately 60 percent of the total dose of 300,000 units is excreted in the urine within this 5-hour period.
For this reason, high and frequent doses are required to maintain the elevated serum levels desirable in treating certain severe infections in individuals with normal kidney function. In neonates and young infants, and in individuals with impaired kidney function, excretion is considerably delayed. After an intravenous infusion of penicillin G, peak serum concentrations are attained immediately after completion of the infusion.
In a study of ten patients administered a single 5 million unit dose of penicillin G intravenously over 3–5 minutes, the mean serum concentrations were 400 mcg/mL, 273 mcg/mL and 3.0 mcg/mL at 5–6 minutes, 10 minutes and 4 hours after completion of the injection, respectively. In a separate study, five healthy adults were administered one million units of penicillin G intravenously, either as a bolus over 4 minutes or as an infusion over 60 minutes. The mean serum concentration eight minutes after completion of the bolus was 45 mcg/mL and eight minutes after completion of the infusion was 14.4 mcg/mL.
The mean β-phase serum half-life of penicillin G administered by the intravenous route in ten patients with normal renal function was 42 minutes, with a range of 31–50 minutes. The clearance of penicillin G in normal individuals is predominantly via the kidney. The renal clearance, which is extremely rapid, is the result of glomerular filtration and active tubular transport, with the latter route predominating.
Urinary recovery is reported to be 58–85% of the administered dose. Renal clearance of penicillin is delayed in premature infants, neonates and in the elderly due to decreased renal function. The serum half-life of penicillin G correlates inversely with age and clearance of creatinine and ranges from 3.2 hours in infants 0 to 6 days of age to 1.4 hours in infants 14 days of age or older.
Nonrenal clearance includes hepatic metabolism and, to a lesser extent, biliary excretion. The latter routes become more important with renal impairment. Probenecid blocks the renal tubular secretion of penicillin.
Therefore, the concurrent administration of probenecid prolongs the elimination of penicillin G and, consequently, increases serum concentrations. Penicillin G is distributed to most areas of the body including lung, liver, kidney, muscle, bone and placenta. In the presence of inflammation, levels of penicillin in abscesses, middle ear, pleural, peritoneal and synovial fluids are sufficient to inhibit most susceptible bacteria.
Penetration in the eye, brain, cerebrospinal fluid (CSF) or prostate is poor in the absence of inflammation. With inflamed meninges, the penetration of penicillin G into the CSF improves, such that the CSF/serum ratio is 2–6%. Inflammation also enhances its penetration into the pericardial fluid.
Penicillin G is actively secreted into the bile resulting in levels at least 10 times those achieved simultaneously in serum. Penicillin G penetrates poorly into human polymorphonuclear leukocytes. In the presence of impaired renal function, the β-phase serum half-life of penicillin G is prolonged. β-phase serum half-lives of one to…
📦 How Supplied / Storage and Handling ▾
HOW SUPPLIED Buffered Pfizerpen ® (Penicillin G Potassium for Injection, USP) is available in vials containing respectively 5,000,000 units × 10's (NDC 0049-0520-22) and 20,000,000 units × 1's (NDC 0049-0530-22); buffered with sodium citrate and citric acid to an optimum pH. Each million units contains approximately 6.8 milligrams of sodium (0.3 mEq) and 65.6 milligrams of potassium (1.68 mEq). Store the dry powder below 86°F (30°C).
📦 Storage and Handling ▾
Store the dry powder below 86°F (30°C).
📋 Description ▾
DESCRIPTION Buffered Pfizerpen (Penicillin G Potassium for Injection, USP) is a sterile, pyrogen-free powder for reconstitution. Buffered Pfizerpen for Injection is an antibacterial agent for intramuscular, continuous intravenous infusion, intrapleural or other local infusion, and intrathecal administration. Each million units contains approximately 6.8 milligrams of sodium (0.3 mEq) and 65.6 milligrams of potassium (1.68 mEq).
Buffered Pfizerpen (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. Chemically, Pfizerpen is monopotassium 3,3-dimethyl-7-oxo-6-(2-phenylacetamido)-4-thia-1-azabicyclo (3.2.0) heptane-2-carboxylate. It has a molecular weight of 372.48 and the following chemical structure: Formula C 16 H 17 KN 2 O 4 S Penicillin G potassium is a colorless or white crystal, or a white crystalline powder which is odorless, or practically so, and moderately hygroscopic.
Penicillin G potassium is very soluble in water. The pH of the reconstituted product is between 6.0–8.5. Chemical Structure
💬 Information for Patients ▾
Information for Patients Patients should be counseled that antibacterial drugs including Penicillin G Potassium for Injection should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When Penicillin G Potassium for Injection is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed.
Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by Penicillin G Potassium for Injection or other antibacterial drugs in the future. Diarrhea is a common problem caused by antibiotics which usually ends when the antibiotic is discontinued. Sometimes after starting treatment with antibiotics, patients can develop watery and bloody stools (with or without stomach cramps and fever) even as late as two or more months after having taken the last dose of the antibiotic.
If this occurs, patients should contact their physician as soon as possible.