Absorption, Distribution and Excretion
After oral administration, less than 1% is absorbed via the gastrointestinal tract. It is completely absorbed after intramuscular injection. In healthy subjects, aztreonam is primarily excreted in the urine via active tubular secretion and glomerular filtration, in roughly equal proportions. Urinary excretion is essentially complete within 12 hours after a single parenteral dose. 12.6 L 91 mL/min [Health]

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Metabolism/Metabolites Approximately 6% to 16% of aztreonam is metabolized to inactive metabolites via β-lactam bond hydrolysis, forming open-ring compounds.

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Biological Half-Life In subjects with normal renal function, the mean serum half-life of aztreonam is 1.7 hours (1.5 to 2.0 hours), regardless of dose. The mean serum half-life of aztreonam is increased in elderly patients and patients with impaired renal function (4.7 to 6 hours and 2.1 hours, respectively).

Hepatotoxicity
The systemic toxicity of aztreonam is similar to other β-lactam antibiotics, but it is unclear whether it will cause liver injury like penicillins or cephalosporins. Asymptomatic elevations of serum transaminases are common (10% to 38%) during high-dose intravenous aztreonam treatment. These enzyme abnormalities are usually mild to moderate, asymptomatic, and resolve spontaneously without discontinuation of the drug. The incidence of enzyme elevations during aztreonam treatment is slightly higher than with other antibiotics in the same class. Such cases are extremely rare because there are no reported cases of significant liver injury and jaundice caused by aztreonam. Therefore, there is currently no data on the latency period or pattern of liver injury. There have been reports of significant transaminase elevations within 3 to 5 days after starting aztreonam, but these cases were without jaundice and returned to normal rapidly after discontinuation of the drug. Probability Score: E (Unlikely to be the cause of clinically significant liver injury).

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Effects during pregnancy and lactation
◉ Overview of use during lactation
Limited information suggests that the concentration of aztreonam in breast milk is low and is not expected to have adverse effects on breastfed infants. There have been reports that β-lactam antibiotics occasionally disrupt the gut microbiota of infants, leading to diarrhea or thrush, but these effects have not been fully assessed. A working group of respiratory experts from Europe, Australia, and New Zealand found that inhaled tobramycin is compatible with breastfeeding. Aztreonam 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
The average serum protein binding rate is 56%, regardless of dose. In cases of impaired renal function, the binding rate is 36% to 43%.

2-[[1-(2-amino-4-thiazolyl)-2-[[(2S,3S)-2-methyl-4-oxo-1-sulfo-3-azacyclobutyl]amino]-2-oxoethylidene]amino]oxo-2-methylpropionic acid is a monocyclic β-lactam antibiotic. It is a monocyclic β-lactam antibiotic, originally isolated from Chromobacterium violaceum. It is resistant to β-lactamases and is used to treat Gram-negative bacterial infections, particularly those of the meninges, bladder, and kidneys. It may cause superinfection with Gram-positive bacteria. Aztreonam is a parenteral synthetic monocyclic β-lactam antibiotic with specific activity against aerobic Gram-negative bacilli and resistance to multiple β-lactamases. Aztreonam treatment is usually accompanied by a mild elevation of serum transaminase levels, but without symptoms; no clinically significant liver damage has been reported. Aztreonan is a monocyclic β-lactam antibiotic, originally isolated from Chromobacterium violaceum, and possesses bactericidal activity. Aztreonan preferentially binds to and inactivates penicillin-binding protein-3 (PBP-3), which is involved in bacterial cell wall synthesis, thereby inhibiting bacterial cell wall integrity, leading to cell lysis and death. Unlike other β-lactam antibiotics, aztreonan is resistant to β-lactamase hydrolysis and is commonly used to treat infections caused by Gram-negative aerobic microorganisms. It is a monocyclic β-lactam antibiotic originally isolated from Chromobacterium violaceum. It is resistant to β-lactamases and is used to treat Gram-negative bacterial infections, particularly those of the meninges, bladder, and kidneys. It may cause superinfection with Gram-positive bacteria. See also: aztreonan (note moved to). Drug Indications Cayston is indicated for the treatment of the following infections caused by susceptible Gram-negative bacteria: urinary tract infections, lower respiratory tract infections, sepsis, skin and soft tissue infections, intra-abdominal infections, and gynecological infections. FDA Label Cayston is indicated for the treatment of chronic lung infections caused by Pseudomonas aeruginosa in patients aged 6 years and older with cystic fibrosis (CF). Official guidelines for the rational use of antimicrobial agents should be considered. Treatment of Pseudomonas aeruginosa lung infections/colonization in patients with cystic fibrosis Treatment of Gram-negative intrabronchial infections in patients with bronchiectasis Mechanism of Action Aztreonam's bactericidal action stems from its high affinity for penicillin-binding protein 3 (PBP3), thereby inhibiting bacterial cell wall synthesis. Aztreonam inhibits the third (and final) stage of bacterial cell wall synthesis by binding to PBP3. Subsequently, bacterial cell wall autolysins (such as autolysins) mediate cell lysis. Aztreonam may interfere with the action of autolysin inhibitors.

435.051

99341-02-3

5459211

Typically exists as solid at room temperature

1.83±0.1 g/cm3 (20 °C, 760 mmHg)

-0.66

4

12

7

28

808

2

WZPBZJONDBGPKJ-IYZXUIDESA-N

InChI=1S/C13H17N5O8S2/c1-5-7(10(20)18(5)28(23,24)25)16-9(19)8(6-4-27-12(14)15-6)17-26-13(2,3)11(21)22/h4-5,7H,1-3H3,(H2,14,15)(H,16,19)(H,21,22)(H,23,24,25)/b17-8+/t5-,7-/m0/s1

2-[(E)-[1-(2-amino-1,3-thiazol-4-yl)-2-[[(2S,3S)-2-methyl-4-oxo-1-sulfoazetidin-3-yl]amino]-2-oxoethylidene]amino]oxy-2-methylpropanoic 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.)