BUFFERED PENICILLIN G POTASSIUM 5000000 [iU]/1 Injection, Powder, For Solution, 1 injection — NDC 51662-1436-1 (Billing 51662-1436-01)
This is a package of 1 injection of BUFFERED PENICILLIN G POTASSIUM 5000000 [iU]/1 Injection, Powder, For Solution from HF Acquisition Co LLC, DBA HealthFirst, no longer marketed (first marketed Jan 2020), no longer in the FDA NDC Directory. It is this product's only package size.
Identity & classification
Regulatory identifiers FDA, NLM and CMS codes for this package
- RxCUI (RxNorm): 863538
Where does this data come from?
- FDA openFDA NDC Directory · synced Oct 1, 2026
- FDA label on DailyMed · label index refreshed Oct 1, 2026
- RxNorm (NLM RxNav) · catalog refreshed Oct 1, 2026
- Medi-Span GPI (licensed)
- First Databank (licensed) · refreshed Oct 1, 2026
RxNorm drug class
This medicine belongs to the Penicillin-class Antibacterial class.
Where does this data come from?
- RxClass (NLM) · catalog refreshed Oct 1, 2026
Clinical
- It treats serious bacterial infections, such as pneumonia, meningitis, endocarditis, blood infections, anthrax and syphilis. It only works on susceptible bacteria, not viruses.
- A healthcare professional gives it into a vein or muscle. It is usually given every 4 to 6 hours because your body clears it quickly. Your prescriber decides the exact schedule.
- Pain at the injection site, vein irritation, nausea and rash can happen. If you are being treated for syphilis, you may get fever, chills and aches for 12 to 24 hours.
- Get emergency help for trouble breathing, swelling of the face or throat, hives or fainting. Also report a severe skin rash, seizures, or diarrhea that develops during or even week...
Patient education
Supplement & herbal interactions
Where does this data come from?
- MedlinePlus (NLM) · refreshed Oct 1, 2026
- FDA label on DailyMed · label index refreshed Oct 1, 2026
Ask a licensed pharmacist directly — free, answered by our team.
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 · Q2 2026 | $38.82 | — |
| Medicare Part B allowsASP · J2540 | $0.637 / J2540 unit | — |
Where does this data come from?
- CMS NADAC weekly file
- CMS ASP pricing files · refreshed Sep 20, 2026
- CMS Medicaid State Drug Utilization Data · refreshed Oct 3, 2026
- CMS Part D plan pricing files · refreshed Sep 24, 2026
- VA National Acquisition Center price file
Billing & reimbursement
Where does this data come from?
- CMS ASP NDC-HCPCS crosswalk · refreshed Sep 22, 2026
- DMEPDAC NDC-HCPCS crosswalk
- openFDA NSDE billing units · refreshed Sep 7, 2026
Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Marketing end | Status |
|---|---|---|---|---|
| 51662-1436-01 You're viewing this Main listing | 1 INJECTION, POWDER, FOR SOLUTION in 1 VIAL | 2020-01-29 | — | Discontinued by firm |
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] 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]this 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?
- FDA openFDA NDC Directory · synced Oct 1, 2026
- FDA Orange Book · refreshed Sep 3, 2026
- CMS NADAC weekly file
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?
- FDA Orange Book · refreshed Sep 3, 2026
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.
Where does this data come from?
IACT rows and label-wide narrative are kept separate; availability and product-level specificity depend on the submitted label.- FDA label on DailyMed · label index refreshed Oct 1, 2026
- FDA openFDA NDC Directory · synced Oct 1, 2026
Inactive ingredient FAQ
Are inactive ingredients the same for every manufacturer?
Why might an inactive ingredient be missing?
Can inactive ingredients matter?
Manufacturer & labeler
Where does this data come from?
- FDA openFDA NDC Directory · synced Oct 1, 2026
- Drugs@FDA
Full prescribing information FDA SPL
🎯 Indications and Usage ▾
INDICATIONS & USAGE Therapy Buffered 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 Buffered 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.
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.
INDICATIONS
⏱️ Dosage and Administration ▾
DOSAGE & ADMINISTRTION Buffered Penicillin G Potassium for Injection, USP may be given intravenously or intramuscularly. The usual dose recommendations are as follows: Pediatric patients This product should not be administered to patients requiring less than one million units per dose. (see PRECAUTIONS – Pediatric Use).
Renal Impairment Penicillin G is relatively nontoxic, and dosage adjustments are generally required only in cases of severe renal impairment. The recommended dosage regimens are as follows: Creatinine clearance less than 10 mL/min/1.73m2; administer a full loading dose (see recommended dosages in the tables above) followed by one-half of the loading dose every 8 to 10 hours. Uremic patients with a creatinine clearance greater than 10 mL/min/1.73m2; administer a full loading dose (see recommended dosages in the tables above) followed by one-half of the loading dose every 4 to 5 hours.
Additional dosage modifications should be made in patients with hepatic disease and renal impairment. For most acute infections, treatment should be continued for at least 48 to 72 hours after the patient becomes asymptomatic. Antibiotic therapy for Group A β-hemolytic streptococcal infections should be maintained for at least 10 days to reduce the risk of rheumatic fever.
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution and container permit. Preparation of Solution Solutions of penicillin should be prepared as follows: Loosen powder. Hold vial horizontally and rotate it while slowly directing the stream of diluent against the wall of the vial.
Shake vial vigorously after all the diluent has been added. Depending on the route of administration, use Sterile Water for Injection, USP or Sterile Isotonic Sodium Chloride Solution for Parenteral use. Note: Penicillins are rapidly inactivated in the presence of carbohydrate solutions at alkaline pH.
Reconstitution The following table shows the amount of solvent required for solution of various concentrations: When the required volume of solvent is greater than the capacity of the vial, the penicillin can be dissolved by first injecting only a portion of the solvent into the vial, then withdrawing the resultant solution and combining it with the remainder of the solvent in a larger sterile container. Penicillin G Potassium for Injection, USP is highly water soluble. It may be dissolved in small amounts of Water for Injection, or Sterile Isotonic Sodium Chloride Solution for Parenteral Use.
All solutions should be stored in a refrigerator. When refrigerated, penicillin solutions may be stored for seven days without significant loss of potency. Buffered Penicillin G Potassium for Injection may be given intramuscularly or by continuous intravenous drip for dosages of 500,000, 1,000,000 or 5,000,000 units.
It is also suitable for intrapleural, intraarticular, and other local installations. THE 20,000,000 UNIT (20 MILLION UNIT) DOSAGE MAY BE ADMINISTERED BY INTRAVENOUS INFUSION ONLY. (1) Intramuscular Injection: Keep total volume of injection small.
The intramuscular route is the preferred route of administration. Solutions containing up to 100,000 units of penicillin per mL of diluent may be used with a minimum of discomfort. Greater concentration of penicillin G per mL is physically possible and may be employed where therapy demands.
When large doses are required, it may be advisable to administer aqueous solutions of penicillin by means of continuous intravenous drip. (2) Continuous Intravenous Drip: Determine the volume of fluid and rate of its administration required by the patient in a 24-hour period in the usual manner for fluid therapy, and add the appropriate daily dosage of penicillin to this fluid. For example, if an adult patient requires 2 liters of fluid in 24 hours and a daily dosage of 10 million units of penicillin, add 5 million units of 1 liter and adjust the rate of flow so the liter will…
⛔ Contraindications ▾
CONTRAINDICATIONS A history of hypersensitivity (anaphylactic) reaction to any penicillin is a contraindication.
⚠️ Warnings ▾
WARNINGS 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. SERIOUS ANAPHYLACTIC REACTIONS REQUIRE IMMEDIATE EMERGENCY TREATMENT WITH EPINEPHRINE.
OXYGEN, INTRAVENOUS STEROIDS, AND AIRWAY MANAGEMENT, INCLUDING INTUBATION, SHOULD ALSO BE ADMINISTERED AS INDICATED. Pseudomembranous colitis has been reported with nearly all antibacterial agents, including penicillin G, and may range in severity from mild to life-threatening. Therefore, it is important to consider this diagnosis in patients who present with diarrhea subsequent to the administration of antibacterial agents.
Treatment with antibacterial agents alters the normal flora of the colon and may permit overgrowth of clostridia. Studies indicate that a toxin produced by Clostridium difficile is one primary cause of “antibiotic-associated colitis”. After the diagnosis of pseudomembranous colitis has been established, therapeutic measures should be initiated.
Mild cases of pseudomembranous colitis usually respond to drug discontinuation alone. In moderate to severe cases, consideration should be given to management with fluids and electrolytes, protein supplementation and treatment with an antibacterial drug effective against C. difficile.
🤒 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 to 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, hyperventiliation, vasodilation with flushing and mild hypotension.
The pathogenesis of the Herxheimer reaction may be due to the release from the spirochaete of host 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 angloneurotic 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; Coombspositive 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 Buffered Penicillin G Potassium for Injection, USP (1 million units contains 0.3 mEq of sodium and 1.68 mEq of potassium) 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 with intravenous administration.
🆘 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 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 to 5 minutes, the mean serum concentrations were 400 mcg/mL, 273 mcg/mL and 3 mcg/mL at 5 to 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 to 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 to 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 the 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 into 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 to 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 two hours were observed in azotemic patients with serum creatinine concentrations <3 mg/100 mL and ranged as high as 20 hours in anuric patients. A linear relationship, including the lowest range of renal function, is found between the serum elimination rate constant and renal function as measured by creatinine clearance. In patients with altered renal function, the presence of hepatic insufficiency further alters the elimination of penicillin G.
In one study, the serum half-lives in two anuric patients (excreting <400 mL urine/day) were 7.2 and 10.1 hours. A totally anuric patient with terminal hepatic cirrhosis had a penicillin half-life of 30.5 hours, while another patient with anuria and liver disease had a serum half-life of 16.4 hours. The dosage of penicillin G should be reduced in patients with severe renal impairment, with additional modifications when hepatic disease accompanies the renal impairment.
Hemodialysis has been shown to reduce penicillin G serum levels. Microbiology Penicillin G is bactericidal against penicillin-susceptible microorganisms during the stage of active multiplication. It acts by i…
📦 How Supplied / Storage and Handling ▾
HOW SUPPLIED BUFFERED PENICILLIN G POTASSIUM FOR INJECTION, USP is supplied in the following dosage forms. NDC 51662-1436-1 BUFFERED PENICILLIN G POTASSIUM FOR INJECTION, USP 5,000,000 UNITS (5 MILLION UNITS) HF Acquisition Co LLC, DBA HealthFirst Mukilteo, WA 98275 Also supplied in the following manufacture supplied dosage forms Buffered Penicillin G Potassium for Injection, USP, is supplied in dry powder form in vials containing 1,000,000 units (1 million units) × 10’s (NDC 0781-6134-95), 5,000,000 units (5 million units) × 10’s (NDC 0781-6135-95), and 20,000,000 units (20 million units) × 1’s (NDC 0781-6136-94) of crystalline penicillin G as the potassium salt; buffered with sodium citrate and citric acid to an optimum pH.
STORAGE Store the dry powder at 20° to 25°C (68° to 77°F) [see USP controlled room temperature]. Sterile constituted solution may be kept in refrigerator 2° to 8°C (36° to 46°F) for 7 days without significant loss of potency.
📋 Description ▾
DESCRIPTION Buffered Penicillin G Potassium for Injection, USP is sterile penicillin G potassium powder for reconstitution. It is an antibacterial agent intended for intravenous or intramuscularly use. Chemically, Penicillin G Potassium is monopotassium (2S,5R,6R)-3,3-dimethyl-7-oxo-6-(2-phenylacetamido)-4-thia-1-azabicyclo (3.2.0) heptane-2-carboxylate, and has the following chemical structure: Penicillin G potassium, a water soluble benzylpenicillin, is a white to almost white crystalline powder which is almost odorless and/or after reconstitution a colorless solution.
The pH of freshly constituted solutions usually ranges from 6 to 8.5. Sodium citrate and citric acid have been added as a buffer. Buffered Penicillin G Potassium for Injection, USP is supplied in vials equivalent to 1,000,000 units (1 million units), 5,000,000 units (5 million units), or 20,000,000 units (20 million units) of penicillin G as the potassium salt.
Each million unit contains approximately 7.9 milligrams of sodium (0.34 mEq) and 65.6 milligrams of potassium (1.68 mEq). STRUCTURE
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 | — Not published for this NDC No photo available yet for this listing. |
| Inactive ingredients (structured) | — Not published for this NDC The labeler did not submit a structured excipient list, or no SPL is 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 | — Not published for this NDC Applies only to products approved under an NDA/ANDA; many listings are out of scope. |
| 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. |