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 primarily absorbed through glomerular filtration and active tubular secretion, and is rapidly excreted in the urine as the unchanged drug. Biological Half-Life 20 to 30 minutes

Hepatotoxicity
Oxacillin is associated with two types of hepatotoxicity: the first is an acute, transient increase in serum transaminase levels following high-dose intravenous treatment; the second is a longer-lasting, usually cholestatic, specific liver injury, similar to the hepatotoxicity of other second-generation penicillins such as dicloxacillin, flucloxacillin, and nafcillin. High-dose intravenous oxacillin typically causes elevated serum ALT levels, increasing to 2 to 20 times the upper limit of normal after 1 to 3 weeks of treatment. Alkaline phosphatase levels are only slightly elevated. Fever and nonspecific symptoms such as abdominal pain and nausea may occur, but these are usually absent. Eosinophilia may occur in some patients, but rash and arthralgia are uncommon. Serum transaminase levels rapidly return to normal within 1 to 2 weeks after discontinuation of oxacillin or switching to a lower dose (especially oral formulations). Jaundice does not occur. This reaction does not appear to cross-react with natural penicillins, clindamycin, or even nafcillin. Intravenous carbenicillin can cause a similar syndrome. This hepatotoxicity may be more common in HIV-infected individuals than in uninfected individuals. In addition to the asymptomatic elevated serum transaminase syndrome commonly seen during high-dose intravenous therapy, oxacillin may (but rarely) cause cholestatic hepatitis that lasts longer, typically appearing 1 to 6 weeks after treatment initiation and potentially lasting weeks to months. This specific liver injury is similar to that caused by dicloxacillin and other second-generation penicillins. Immune hypersensitivity symptoms such as rash, fever, and eosinophilia may occur, but are not prominent. Autoantibodies are not detected. Liver injury may persist for a long time, but usually resolves within 1 to 2 months of onset. Liver biopsy typically shows cholestatic hepatitis with mixed inflammatory infiltration. Probability score: B (Possibly a rare cause of clinically significant liver injury).

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Effects during pregnancy and lactation
◉ Overview of medication use during lactation
Limited information suggests that oxacillin concentrations in breast milk are low and 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. Oxacillin can be used in breastfeeding women.
◉ Effects on breastfed infants
No published information found as of the revision date.
◉ Effects on lactation and breast milk
No published information found as of the revision date.

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Protein binding rate
94.2 +/- 2.1% (bound to serum proteins, primarily 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 with a 5-methyl-3-phenylisoxazole-4-carboxamide group at the 6β position. It is an antibacterial agent and antimicrobial drug. It is the conjugate acid of oxacillin(1-). It is an antibiotic similar to flucloxacillin used to treat drug-resistant staphylococcal infections. Oxacillin belongs to the penicillin class of antimicrobial drugs. Oxacillin is an injectable second-generation penicillin antibiotic used to treat moderate to severe penicillinase-resistant staphylococcal infections. Oxacillin has been associated with rare cases of clinically significant specific liver injury, but more commonly causes transient elevations in serum transaminases without jaundice. Oxacillin has been reported in bovine (Bos taurus), Cordyceps farinosa, and Liquidambar formosana, with relevant data. Oxacillin is a semi-synthetic, penicillinase-resistant, and acid-resistant penicillin antibiotic with antibacterial activity. Oxacillin binds to penicillin-binding proteins in the bacterial cell wall, thereby blocking the synthesis of peptidoglycan (a key component of the bacterial cell wall). This leads to inhibited cell growth and ultimately cell lysis. Oxacillin sodium is the sodium salt form of oxacillin, a semi-synthetic, penicillinase-resistant, and acid-resistant penicillin antibiotic with antibacterial activity. Oxacillin binds to penicillin-binding proteins in the bacterial cell wall, thereby blocking the synthesis of peptidoglycan, a key component of the bacterial cell wall. This leads to inhibited cell growth and ultimately cell lysis. An antibiotic similar to flucloxacillin, used to treat drug-resistant staphylococcal infections. See also: Oxacillin sodium (salt form); Oxacillin benzylcin (its active ingredient). Indications: For the treatment of drug-resistant staphylococcal infections. Mechanism of Action: Oxacillin inhibits the third (and final) stage of bacterial cell wall synthesis by binding to specific penicillin-binding proteins (PBPs) located within the bacterial cell wall. Subsequently, bacterial cell wall autolysins (such as autolysins) mediate cell lysis; oxacillin may interfere with the action of autolysin inhibitors.

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Pharmacodynamics
Oxacillin is a penicillin-type β-lactam antibiotic used to treat bacterial infections caused by susceptible bacteria (usually Gram-positive bacteria). The term "penicillin" can refer to several available penicillin derivatives or to antibiotics derived from penicillin. Oxacillin has in vitro activity against Gram-positive and Gram-negative aerobic and anaerobic bacteria. Oxacillin's bactericidal activity derives from its inhibition of cell wall synthesis and exerts its effect through binding to penicillin-binding proteins (PBPs). Oxacillin is stable against the hydrolytic activity of various β-lactamases, including penicillinase, cephalosporinase, and extended-spectrum β-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.)