β-lactam

At minimum inhibitory concentrations (MICs) of 0.05, 0.09, 0.32, and 0.80 μg/mL, oxycillin inhibits gram-positive pathogens such as group A streptococci, pneumotocci, susceptible staphylococci, and penicillin-resistant staphylococci, respectively[1]. The isolates resistant to oxacillin also exhibit strong resistance to other penicillins [1].

In mice infected with Staphylococcus aureus Evans, oxacillin (50-800 mg/kg; sc; once) has a curative dose (CD50) of 253.3 mg/kg. Oxacillin has a CD50 oral of 187.2 mg/kg[2].

Animal/Disease Models: CD-1 strain male albino mice infected with S. aureus Evans[2]
Doses: 50, 100, 200, 400 and 800 mg/kg
Route of Administration: subcutaneous (sc)injection , once
Experimental Results: demonstrated therapeutic activity with CD50 of 253.3 mg/kg.

Absorption, Distribution and Excretion
Oxacillin Sodium is rapidly excreted as unchanged drug in the urine by glomerular filtration and active tubular secretion.

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Biological Half-Life
20 to 30 minutes

Hepatotoxicity
Oxacillin has been linked to two forms of hepatotoxicity, first an acute and transient elevation in serum aminotransferase levels occurring with high doses of intravenous therapy; and second, a more prolonged, usually cholestatic, idiosyncratic liver injury that is similar to the hepatotoxicity of other second-generation penicillins such as dicloxacillin, flucloxacillin, and nafcillin.
High doses of intravenous oxacillin are commonly accompanied by elevations in serum ALT in the range of 2 to 20 times the upper limit of normal arising after 1 to 3 weeks of therapy. Alkaline phosphatase levels are only minimally elevated. Fever and nonspecific symptoms of abdominal pain and nausea can occur, but are often absent. Eosinophilia is present in some patients, but rash and arthralgias are uncommon. Serum aminotransferase levels rapidly fall into the normal range (in 1 to 2 weeks) with discontinuation of oxacillin or switch to lower doses, particularly in oral formulations. Jaundice does not occur. There appears to be no cross reactivity of this response with the natural penicillins, clindamycin or even nafcillin. Intravenous carbenicillin can cause a similar syndrome. This hepatotoxicity may be more common in HIV-positive than noninfected individuals.
In addition to the common syndrome of asymptomatic serum aminotransferase elevations during high dose intravenous therapy, oxacillin can also but rarely lead to a more prolonged usually cholestatic hepatitis that appears 1 to 6 weeks after starting therapy and may persist for weeks to months. This form of idiosyncratic liver injury is similar to that described with dicloxacillin and other second generation penicillins. Immunoallergic features of rash, fever and eosinophilia can occur, but are not prominent. Autoantibodies are not found. The liver injury can be prolonged, but generally resolves within 1 to 2 months of onset. Liver biopsy generally shows a cholestatic hepatitis with mixed inflammatory infiltrates.
Likelihood score: B (likely rare cause of clinically apparent liver injury).

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Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
Limited information indicates that oxacillin produces low levels in milk that are not expected to cause adverse effects in breastfed infants. Occasionally disruption of the infant's gastrointestinal flora, resulting in diarrhea or thrush have been reported with penicillins, but these effects have not been adequately evaluated. Oxacillin is acceptable in nursing mothers.
◉ Effects in Breastfed Infants
Relevant published information was not found as of the revision date.
◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.

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Protein Binding
94.2 +/- 2.1% (binds to serum protein, mainly albumin)

[1]. KIRBY WM, et al. Oxacillin: laboratory and clinical evaluation. JAMA. 1962 Sep 1;181:739-44.
[2]. Yurchenco JA, et al. Nafcillin and oxacillin: comparative antistaphylococcal activity in mice. J Antibiot (Tokyo). 1976 Apr;29(4):460-5.

Oxacillin is a penicillin antibiotic carrying a 5-methyl-3-phenylisoxazole-4-carboxamide group at position 6beta. It has a role as an antibacterial agent and an antibacterial drug. It is a conjugate acid of an oxacillin(1-).
An antibiotic similar to [flucloxacillin] used in resistant staphylococci infections.
Oxacillin is a Penicillin-class Antibacterial.
Oxacillin is a parenteral, second generation penicillin antibiotic that is used to treat moderate-to-severe, penicillinase-resistant staphylococcal infections. Oxacillin has been linked to rare instances of clinically apparent, idiosyncratic liver injury, but it more commonly causes transient elevations in serum aminotransferases without jaundice.
Oxacillin has been reported in Bos taurus, Cordyceps farinosa, and Liquidambar formosana with data available.
Oxacillin is a semisynthetic penicillinase-resistant and acid-stable penicillin with an antimicrobial activity. Oxacillin binds to penicillin-binding proteins in the bacterial cell wall, thereby blocking the synthesis of peptidoglycan, a critical component of the bacterial cell wall. This leads to inhibition of cell growth and causes cell lysis.
Oxacillin Sodium is the sodium salt form of oxacillin, a semisynthetic penicillinase-resistant and acid-stable penicillin with an antimicrobial activity. Oxacillin binds to penicillin-binding proteins in the bacterial cell wall, thereby blocking the synthesis of peptidoglycan, a critical component of the bacterial cell wall. This leads to inhibition of cell growth and causes cell lysis.
An antibiotic similar to FLUCLOXACILLIN used in resistant staphylococci infections.
See also: Oxacillin Sodium (has salt form); Oxacillin benzathine (is active moiety of).

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Drug Indication
Used in the treatment of resistant staphylococci infections.

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Mechanism of Action
By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, Oxacillin inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that Oxacillin interferes with an autolysin inhibitor.

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Pharmacodynamics
Oxacillin is a penicillin beta-lactam antibiotic used in the treatment of bacterial infections caused by susceptible, usually gram-positive, organisms. The name "penicillin" can either refer to several variants of penicillin available, or to the group of antibiotics derived from the penicillins. Oxacillin has in vitro activity against gram-positive and gram-negative aerobic and anaerobic bacteria. The bactericidal activity of Oxacillin results from the inhibition of cell wall synthesis and is mediated through Oxacillin binding to penicillin binding proteins (PBPs). Oxacillin is stable against hydrolysis by a variety of beta-lactamases, including penicillinases, and cephalosporinases and extended spectrum beta-lactamases.

C19H19N3O5S

401.44

401.105

66-79-5

Oxacillin sodium monohydrate;7240-38-2;Oxacillin sodium salt;1173-88-2;Oxacillin-d5

6196

Typically exists as solid at room temperature

188ºC

2.224

2

7

4

28

681

3

CC1=C(C(N[C@@H]2C(N3[C@H](C(C)(S[C@H]23)C)C(O)=O)=O)=O)C(C4=CC=CC=C4)=NO1

UWYHMGVUTGAWSP-JKIFEVAISA-N

InChI=1S/C19H19N3O5S/c1-9-11(12(21-27-9)10-7-5-4-6-8-10)15(23)20-13-16(24)22-14(18(25)26)19(2,3)28-17(13)22/h4-8,13-14,17H,1-3H3,(H,20,23)(H,25,26)/t13-,14+,17-/m1/s1

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

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.)