Absorption, Distribution and Excretion
Penicillin G is rapidly absorbed after both intramuscular and subcutaneous injection. Initial blood concentrations are high after parenteral administration, but the duration of absorption is short. In healthy individuals on an empty stomach, oral absorption is only about 15-30% because it is readily hydrolyzed by acid. Penicillin G is primarily excreted via the kidneys. Non-renal clearance routes include hepatic metabolism and a small amount of bile excretion. The daily blood concentration in adults with normal renal function is 0.53-0.67 L/kg. The daily blood concentration in healthy individuals is 560 ml/min. …Widely distributed throughout the body…its apparent volume of distribution accounts for approximately 50% of total body fluids. Over 90% of the drug in the blood is found in plasma, and less than 10% is found in red blood cells; approximately 65% is reversibly bound to plasma albumin. Low protein concentration…low binding degree…drug efficacy. Significant active drug components are found in the liver, bile, kidneys, semen, lymph, and intestines. ...When the meninges are normal, penicillin does not readily enter the cerebrospinal fluid. After oral administration of 500 mg potassium penicillin, the urinary penicillin concentration is 600 μg/mL within 2 hours and 300 μg/mL within 4 hours. ...The low placental transport efficiency is consistent with the low lipid solubility and low ionization constant of penicillin G, and there is no evidence of placental transport. ...It is rapidly cleared from the body, primarily through the kidneys, but in small amounts through bile and other routes. Due to incomplete renal development, clearance is significantly lower in newborns and infants... For more complete data on the absorption, distribution, and excretion of penicillin G (21 types), please visit the HSDB records page.

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Metabolism/Metabolites
Approximately 16-30% of the intramuscular dose is metabolized to penicillic acid, an inactive metabolite. Small amounts of 6-aminopenicillanic acid have been detected in the urine of patients taking penicillin G. Small amounts of the drug appear to be hydroxylated into one or more active metabolites, which are also excreted in the urine. Approximately 16-30% of intramuscularly injected penicillin G sodium is metabolized to penicillic acid, which is microbiologically inactive. Small amounts of 6-aminopenicillanic acid (6-APA) have also been found in the urine of patients treated with penicillin G. Furthermore, the drug appears to undergo minor hydroxylation, generating one or more microbiologically active metabolites, which are also excreted in the urine.
Biological Half-Life
The biological half-life of penicillin in adults with normal renal function is reported to be 0.4-0.9 hours.
The elimination half-life in normal adults is approximately 30 minutes.
The half-life of penicillin in human serum increases from approximately 25 minutes in young adults to 2 hours in older adults, and drugs actively secreted by the renal tubules also have a significantly prolonged half-life. /Penicillin/
The half-life of penicillin G in the serum of adults with normal renal function is reported to be 0.4-0.9 hours.
The half-life of penicillin G in neonatal serum is inversely proportional to age and appears to be independent of birth weight. According to reports, the serum half-life of newborns aged 6 days and under is 3.2-3.4 hours, that of newborns aged 7-13 days is 1.2-2.2 hours, and that of newborns aged 14 days and over is 0.9-1.9 hours.

Use of Penicillin G During Pregnancy and Lactation ◉ Overview of Use During Lactation
Limited information suggests that low concentrations of penicillin G in breast milk are not expected to have adverse effects on breastfed infants. There are reports that penicillin-type drugs occasionally disrupt the infant's gut microbiota, leading to diarrhea or thrush, but these effects have not been fully assessed. Penicillin G is safe for use by breastfeeding women. ◉ Effects on Breastfed Infants
A one-month-old breastfed infant with congenital syphilis developed a Herxheimer reaction 6 hours after his mother received an intramuscular injection of 2.4 million units of benzathine penicillin G. However, the infant also received 10 units of penicillin G concurrently with the mother's injection. This reaction was likely caused by penicillin in the breast milk. ◉ Effects on Lactation and Breast Milk
No relevant published information was found as of the revision date.

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Protein Binding
Bound to serum proteins (45-68%), primarily albumin.

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Interaction
A 49-year-old male patient reported that high-dose parenteral administration of penicillin G significantly enhanced the hypoprothrombinemia effect of warfarin. Penicillin G induces a warfarin-protein binding substitution interaction.
Penicillin is generally inactivated in the presence of high temperatures, alkaline or acidic pH, oxidants, alcohols, ethylene glycols, and metal ions such as copper, mercury, or zinc. Currently marketed penicillin drugs will completely lose their antibacterial activity if any part of their core structure (including the β-lactam ring) is broken. The main cause of penicillin inactivation is the hydrolysis of the β-lactam ring. The hydrolysis process and the nature of the degradation products can vary and are generally affected by pH. /Penicillin/
Penicillin G may have physical and/or chemical incompatibility with some drugs, including aminoglycosides and tetracyclines, but this compatibility depends on a variety of factors (e.g., drug concentration, specific diluent used, final pH, temperature).
Penicillin is typically inactivated by high temperatures, alkaline or acidic pH levels, oxidizing agents, alcohols, ethylene glycols, and the presence of metal ions such as copper, mercury, or zinc. Currently marketed penicillin drugs will completely lose their antibacterial activity if any part of the molecular core (including the β-lactam ring) is broken. The main cause of penicillin inactivation is the hydrolysis of the β-lactam ring. The hydrolysis process and the properties of the degradation products can vary and are generally affected by pH. /Penicillin/
For more complete data on the interactions of penicillin G (18 types), please visit the HSDB record page.

Therapeutic Uses

Constipation; GABA modulator; Penicillin
Gingivitis, lung infections, and genital diseases caused by the synergistic effects of Fusobacterium nucleatum (fusiform bacteria) and spirochetes present in the respiratory tract can be easily treated with penicillin. /Penicillin/
Two microorganisms that cause rat-bite fever are sensitive to penicillin G. ...It is the first-line drug for treating mononuclear infections...The only Pasteurella bacteria highly sensitive to penicillin is Pasteurella multocida. The pathogen of erysipelas is sensitive to penicillin.
Penicillin G is almost ideal for treating syphilis; it is a safe, inexpensive, and highly effective drug. ...It is the first-line drug for treating all clinical manifestations of actinomycosis, anthrax, and gas gangrene.
For more complete data on the therapeutic uses of penicillin G (35 types), please visit the HSDB records page.
Drug Warnings

When using high doses of penicillin G sodium, a large sodium load is introduced, which can dilate the extracellular space and may cause edema in patients with heart failure. Penicillin G Sodium: Hypersensitivity reactions to the procaine component are possible, but other toxic effects of procaine are very rare. Anuria can prolong the half-life of penicillin G from the normal 0.5 hours to approximately 10 hours. While penicillin G preparations for inhalation therapy and topical application to the skin and mucous membranes (PrePN) are still available, their use is not recommended due to a lack of sufficient evidence of their efficacy and a high incidence of hypersensitivity reactions. For more complete data on drug warnings for penicillin G (23 in total), please visit the HSDB records page. Pharmacodynamics: Penicillin G is a penicillin-type β-lactam antibiotic used to treat bacterial infections caused by susceptible strains, typically Gram-positive bacteria. The name "penicillin" can refer to several existing penicillin derivatives or to a class of antibiotics derived from penicillin. Penicillin G has in vitro activity against Gram-positive and Gram-negative aerobic and anaerobic bacteria. The bactericidal activity of penicillin G stems from its inhibition of cell wall synthesis and exerts its effect by binding to penicillin-binding proteins (PBPs). Penicillin G is stable against the hydrolytic activity of a variety of β-lactamases, including penicillinase, cephalosporinase, and extended-spectrum β-lactamase.

C16H18N2O4S

334.4

334.098

61-33-6

Penicillin G potassium;113-98-4;Penicillin G sodium salt;69-57-8;Streptomycin;57-92-1;Penicillin G procaine hydrate;6130-64-9;Penicillin G benzathine;1538-09-6;Penicillin G benzathine tetrahydrate;41372-02-5;Penicillin G-d7 potassium;352323-25-2

5904

AMORPHOUS WHITE POWDER

1.4±0.1 g/cm3

663.3±55.0 °C at 760 mmHg

214-217 °C
214 - 217 °C

355.0±31.5 °C

0.0±2.1 mmHg at 25°C

1.655

1.67

2

5

4

23

530

3

CC1([C@@H](N2C([C@@H](NC(CC3=CC=CC=C3)=O)[C@H]2S1)=O)C(O)=O)C

JGSARLDLIJGVTE-MBNYWOFBSA-N

InChI=1S/C16H18N2O4S/c1-16(2)12(15(21)22)18-13(20)11(14(18)23-16)17-10(19)8-9-6-4-3-5-7-9/h3-7,11-12,14H,8H2,1-2H3,(H,17,19)(H,21,22)/t11-,12+,14-/m1/s1

(2S,5R,6R)-3,3-dimethyl-7-oxo-6-[(2-phenylacetyl)amino]-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid

Galofak CilopenBenzylpenicillin Pradupen

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)