Streptococci cannot grow when Penicillin V (0.002-8.0 mg/L) is present; its minimum inhibitory concentrations (MICs) are 0.004-0.008 mg/L[2]. With a MIC50 of 4.0 mg/L and a MIC90 of 8.0 mg/L, Penicillin V (0.002-8.0 mg/L) has antibacterial activity against Clostridium difficile[3]. MIC of 0.016 mg/L, penicillin V (0.004-0.063 mg/L; 18 h) inhibits the development of Staphylococcus aureus[4].

Penicillin V (0.063–0.25 mg/kg; sc) prevents S from growing. in the thigh muscle of mice[4]. Penicillin V (2 mg/kg; sc) had a mean AUC of 0.47 mg/L·h and a plasma half-life of 61 minutes[4]. Rats with acute purulent otitis media (AOM), a fulminant infection, are protected against by penicillin V (100 mg/kg; po once daily for 5 d)[5].

Animal/Disease Models: Specific pathogen free (SPF) male Swiss mice (20-25 g) are inoculated S. aureus[4]
Doses: 0.063, 0.13, 0.25 mg/kg
Route of Administration: Sc
Experimental Results: diminished the number of CFU (1.34×107 counts/mL) compared to controls (3.5×107 counts/mL) at the dose of 0.25 mg/kg.

Absorption, Distribution and Excretion
Following oral administration, phenoxymethylpenicillin is rapidly but incompletely absorbed. The bioavailability of phenoxymethylpenicillin ranges from 25% to 60%. The calcium or potassium salts of phenoxymethylpenicillin exhibit better absorption characteristics compared to the free acid form. Fasting has been reported to enhance drug absorption. Following an oral dose of 125 mg, peak plasma concentrations reach 200 to 700 ng/mL within 2 hours. Following an oral dose of 500 mg, peak plasma concentrations reach 3 to 5 μg/mL within 30 to 60 minutes. Although the drug is rapidly excreted, only 25% of the total dose is detected in the urine. Renal excretion may be delayed in newborns, infants, and patients with renal impairment. The steady-state volume of distribution after intravenous administration is 35.4 liters. The drug is present in small amounts in various tissues, with the highest concentration in the kidneys, and lower concentrations in the liver, skin, and intestines. Phenoxymethylpenicillin has also been detected in cerebrospinal fluid. Phenoxymethylpenicillin has been detected in the placenta and human milk. A dose of 1 million units can achieve a peak plasma concentration of approximately 2 to 3 micrograms per milliliter… In healthy, fasting adults, approximately 60-73% of the oral dose of penicillin V or penicillin V potassium is absorbed via the gastrointestinal tract. In fasting children or adults, the peak serum penicillin V concentration is typically reached within 30-60 minutes after a single oral dose of penicillin V or penicillin V potassium. Compared to free acid, the peak serum penicillin V concentration is reached more quickly and is slightly higher after taking potassium. In one study, in healthy, fasting adults, the mean serum penicillin V concentrations at 30 minutes, 1 hour, 2 hours, and 4 hours after oral administration were 1.2, 1.2, 0.5, and 0.1 micrograms per milliliter, respectively. Following oral administration of a single 250 mg penicillin V tablet to healthy, fasting adults, the mean serum penicillin V concentrations at 30 minutes, 1 hour, 2 hours, and 4 hours post-administration were 2.1–2.8, 2.3–2.7, 0.8–0.9, and 0.1–0.2 μg/mL, respectively. Following oral administration of a single 500 mg penicillin V potassium tablet to healthy, fasting adults, the mean serum penicillin V concentrations at 30 minutes, 1 hour, 2 hours, and 6 hours post-administration were 4.7–5, 4.9–6.3, 2.3–3, and 0.04–0.1 μg/mL, respectively.
Studies assessing the effects of food on the gastrointestinal absorption of penicillin V and penicillin V potassium have yielded mixed results. Most studies indicate that the presence of food in the gastrointestinal tract leads to a decrease and delay in peak serum penicillin V concentrations, but does not affect total drug absorption. However, multiple studies in children aged 2 months to 5 years have shown that peak serum concentrations and the area under the serum concentration-time curve (AUC) are reduced when penicillin V potassium is taken with or immediately after milk or food. For more complete data on the absorption, distribution, and excretion of penicillin V (8 types), please visit the HSDB records page. Metabolites/Metabolites Approximately 35-70% of the oral 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 to one or more active metabolites, which are also excreted in the urine. Following oral administration of penicillin V or penicillin V potassium, approximately 35-70% of the drug is metabolized to non-microbiologically active penicillic acid. Small amounts of 6-aminopenicillanic acid (6-APA) have also been found in the urine of patients taking penicillin V. Furthermore, the drug appears to be slightly hydroxylated to one or more microbiologically active metabolites, which are also excreted in the urine.

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Biological Half-Life
After oral administration, the half-life is approximately 30 minutes. Blood concentrations in patients with renal insufficiency can persist for up to 4 hours. It has been reported that the half-life of penicillin V in the serum of adults with normal renal function is 0.5 hours.

Use of Penicillin V during Pregnancy and Lactation ◉ Overview of Use During Lactation
Limited information suggests that low concentrations of penicillin V 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 V is safe for breastfeeding women.
◉ Effects on Breastfed Infants
In one study, 12 infants were breastfed while their mothers were treated with penicillin V. Seven infants appeared normal, three had loose stools, and one developed a rash on the buttocks on the last day of treatment. These effects may be related to penicillin V in breast milk, but the study did not include a control group. One infant had blood in their stool, but this had occurred once before the mother received penicillin V treatment.
◉ Effects on Lactation and Breast Milk
No relevant published information was found as of the revision date.

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Protein Binding
After oral administration, approximately 50-80% of the drug binds to plasma proteins.Interactions
Oral neomycin has been shown to reduce the absorption of penicillin V….
Because penicillin works by inhibiting cell wall synthesis, drugs that inhibit protein synthesis (e.g., chloramphenicol) may…mask the bactericidal effect of penicillin.
Because penicillin works by inhibiting cell wall synthesis, drugs that inhibit protein synthesis (e.g., erythromycin) may…mask the bactericidal effect of penicillin. …Clinical evidence suggests antagonistic effects between erythromycin and penicillin in patients with group A streptococcal pharyngitis. …While the possibility of antagonism exists, clinical studies have not fully confirmed it.
Tetracyclines…may interfere with the action of bactericidal agents such as penicillin.
For more (complete) data on interactions of penicillin V (16 in total), please visit the HSDB records page.

[1]. Sabath LD. Et, al. Phenoxymethylpenicillin (penicillin V) and phenethicillin. Med Clin North Am. 1970 Sep;54(5):1101-11.
[2]. Kamme C, et, al. In vitro effect on group A streptococci of loracarbef versus cefadroxil, cefaclor and penicillin V. Scand J Infect Dis. 1993;25(1):37-42.
[3]. Norén T, et, al. In vitro susceptibility to 17 antimicrobials of clinical Clostridium difficile isolates collected in 1993-2007 in Sweden. Clin Microbiol Infect. 2010 Aug;16(8):1104-10.
[4]. Overbosch D, et, al. Comparative pharmacodynamics and clinical pharmacokinetics of phenoxymethylpenicillin and pheneticillin. Br J Clin Pharmacol. 1985 May;19(5):657-68.
[5]. Hermansson A, et, al. Prevention of experimental acute otitis media with penicillin V. Acta Otolaryngol. Jan-Feb 1990;109(1-2):119-23.
[6]. Timm A, et al. Photolysis of four β‑lactam antibiotics under simulated environmental conditions: Degradation, transformation products and antibacterial activity. Sci Total Environ. 2019 Feb 15;651(Pt 1):1605-1612.

Therapeutic Uses
Penicillin
Penicillin V is used to treat mild to moderate infections caused by microorganisms susceptible to low concentrations of the drug, or to prevent certain streptococcal infections.
Penicillin V is indicated for the treatment of acute otitis media caused by susceptible microorganisms. (Included on the US product label)
Penicillin V is indicated for the treatment of bacterial pharyngitis caused by susceptible microorganisms. (Included on the US product label)
For more complete therapeutic use data for penicillin V (of 21 types), please visit the HSDB record page.
Drug Warnings

The most important biological effect of penicillin (unrelated to hypersensitivity or "toxic" reactions) is altering the bacterial flora at the site of entry. Regardless of the route of administration, especially oral, penicillin alters the composition of the gut microbiota by eliminating susceptible microorganisms. …In some individuals, this alteration can lead to secondary infections. /Penicillin/
Syphilis patients may experience fever, even vascular failure and death, after using penicillin. This is a manifestation of the Yarish-Herxheimer reaction. This is believed to be due to a hypersensitive reaction to the antigens released during the rapid and massive lysis of spirochetes. /Penicillin/
There have been reports that concurrent use of penicillin can lead to contraceptive failure and pregnancy. …The mechanism is unclear. It has been observed that ampicillin can reduce urinary estriol levels in women in late pregnancy…Phenoxymethylpenicillin has a similar mechanism of action…
Patients with phenylketonuria (i.e., those with a homozygous phenylalanine hydroxylase gene defect) and others who must restrict their phenylalanine intake should note that Penicillin V potassium powder for oral solution, manufactured by WarnerChicco, contains aspartame…After oral administration, aspartame is metabolized to phenylalanine in the gastrointestinal tract.
For more complete data on drug warnings for Penicillin V (16 in total), please visit the HSDB record page.

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Pharmacodynamics
Phenoxymethylpenicillin has a bactericidal effect on penicillin-sensitive microorganisms. It works by interfering with the synthesis of peptidoglycan in the bacterial cell wall during the active reproductive phase of bacteria. In vitro experiments showed that phenoxymethylpenicillin was active against Staphylococcus (except for penicillinase-producing strains), Streptococcus (groups A, C, G, H, L and M), and Pneumococcus, as well as Corynebacterium diphtheriae, Bacillus anthracis, Clostridium, Actinomyces bovis, Streptococcus, Listeria monocytogenes, Leptospira, Neisseria gonorrhoeae, and Treponema pallidum.

C16H18N2O5S

350.39

350.093

87-08-1

Penicillin V Potassium;132-98-9;Penicillin V-d5;1356837-87-0

6869

white, crystalline powder

1.5±0.1 g/cm3

681.4±55.0 °C at 760 mmHg

120 - 128ºC

365.9±31.5 °C

0.0±2.2 mmHg at 25°C

1.651

1.88

2

6

5

24

547

3

C([C@H]1C(C)(C)S[C@@H]2[C@@H](C(N12)=O)NC(=O)COC1C=CC=CC=1)(=O)O

BPLBGHOLXOTWMN-MBNYWOFBSA-N

InChI=1S/C16H18N2O5S/c1-16(2)12(15(21)22)18-13(20)11(14(18)24-16)17-10(19)8-23-9-6-4-3-5-7-9/h3-7,11-12,14H,8H2,1-2H3,(H,17,19)(H,21,22)/t11-,12+,14-/m1/s1

4-Thia-1-azabicyclo(3.2.0)heptane-2-carboxylic acid, 3,3-dimethyl-7-oxo-6-((phenoxyacetyl)amino)-, (2S,5R,6R)-

CCRIS-752CCRIS752 CCRIS 752

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.)