β-lactam

The MICs of 0.05, 0.09, 0.32, and 0.80 μg/mL for group A streptococci, pneumotocci, susceptible staphylococci, and penicillin-resistant staphylococci, respectively, indicate that oxacillin inhibits gram positive pathogens.Other penicillins are severely resistant to the strains that are resistant to oxacillin[1].

Mice infected with Staphylococcus aureus Evans exhibit a curative dose (CD50) of 253.3 mg/kg when treated with oxacillin (50-800 mg/kg; s.c.; once). Oxacillin's oral CD50 is 187.2 mg/kg[2].

Animal Model: S. aureus-infected male albino mice of the CD-1 strain Evans[2]
Dosage: 50, 100, 200, 400 and 800 mg/kg
Administration: Subcutaneous injection, once
Result: demonstrated therapeutic efficacy at a 253.3 mg/kg CD50.

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]. Oxacillin: laboratory and clinical evaluation. JAMA. 1962 Sep 1;181:739-44.

[2]. 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.

C19H18N3NAO5S

423.4188

423.086

C, 53.90; H, 4.29; N, 9.92; Na, 5.43; O, 18.89; S, 7.57

1173-88-2

Oxacillin sodium monohydrate;7240-38-2;Oxacillin;66-79-5;Oxacillin-13C6 sodium

6196

Solid powder

1.49g/cm3

686.8ºC at 760 mmHg

188ºC

369.2ºC

8.32E-20mmHg at 25°C

0.889

2

7

4

28

681

3

S1C(C([H])([H])[H])(C([H])([H])[H])[C@]([H])(C(=O)O[H])N2C([C@]([H])([C@@]12[H])/N=C(/C1=C(C([H])([H])[H])ON=C1C1C([H])=C([H])C([H])=C([H])C=1[H])\[O-])=O.[Na+]

VDUVBBMAXXHEQP-SLINCCQESA-M

InChI=1S/C19H19N3O5S.Na/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)/q+1/p-1/t13-,14+,17-/m1./s1

sodium (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-carboxylate

Oxazocilline;Bactocill,Oxacillin;Oxacillin Sodium;Prostaphlin

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

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

DMSO : 85~125 mg/mL ( 200.74~295.22 mM )
Water : ~85 mg/mL
Ethanol : ~8 mg/mL

Solubility in Formulation 1: ≥ 2.5 mg/mL (5.90 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (5.90 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
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.

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Solubility in Formulation 3: ≥ 2.5 mg/mL (5.90 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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Solubility in Formulation 4: 10% DMSO+40% PEG300+5% Tween-80+45% Saline: ≥ 2.5 mg/mL (5.90 mM)

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