Lomefloxacin targets bacterial DNA gyrase, a type II topoisomerase. This enzyme is involved in the induction or relaxation of supercoiling during DNA replication. By inhibiting DNA gyrase, Lomefloxacin prevents bacterial DNA replication and transcription, leading to cell death. This mechanism is responsible for its broad-spectrum antibacterial activity.

In vitro, Lomefloxacin demonstrates antibacterial activity against a wide range of Gram-positive and Gram-negative bacteria. Its activity is typically assessed using standard susceptibility testing methods, such as broth microdilution or disk diffusion, to determine the minimum inhibitory concentration (MIC) against various bacterial pathogens.

In vivo, Lomefloxacin is used clinically to treat bacterial infections, including bronchitis and urinary tract infections. It is also used for the prophylaxis of UTIs prior to surgery. Its longer half-life allows for once-daily dosing. It is taken orally and is well absorbed.

For in vitro antibacterial susceptibility testing, standard procedures recommended by the Clinical and Laboratory Standards Institute (CLSI) are followed. Bacterial strains are cultured and suspended to a 0.5 McFarland standard. The suspension is inoculated onto Mueller-Hinton agar or into broth containing serial two-fold dilutions of Lomefloxacin. After incubation, the MIC is determined.

For in vitro cell-based assays, the antibacterial activity of Lomefloxacin can be evaluated using cell culture models of infection. Mammalian cell lines are infected with bacterial pathogens in the presence of varying concentrations of the antibiotic. After incubation, bacterial counts are determined. Cytotoxicity to mammalian cells is assessed.

For in vivo animal studies, Lomefloxacin is typically administered orally in rodent models of infection. The compound's efficacy is evaluated against systemic or localized infections caused by susceptible pathogens. Parameters such as survival rates and bacterial load in tissues are assessed.

Absorption, Distribution and Excretion
A single oral dose is rapidly and almost completely absorbed, with approximately 95% to 98% being absorbed. Within 72 hours of discontinuation, lomefloxacin is almost completely excreted in the urine, with approximately 65% excreted unchanged and 9% excreted as its glucuronide metabolites. 271 mL/min/1.73 m2 [creatinine clearance: 110 mL/min/1.73 m2] 31 mL/min/1.73 m2 [creatinine clearance: 0 mL/min/1.73 m2] Metabolism/Metabolites Metabolism is minimal, but five metabolites have been identified in human urine. 65% of the drug is excreted unchanged in the urine, and 9% is excreted as glucuronide metabolites. Biological Half-Life 8 hours
Lomefloxacin is administered orally. It is well absorbed and has a long half-life. It is metabolized in the liver and excreted in urine and feces. Its pharmacokinetics are well characterized.

Use of Lomefloxacin During Pregnancy and Lactation ◉ Overview of Use During Lactation
Lomefloxacin has been discontinued in the United States. There is currently no information regarding the use of lomefloxacin during lactation. Traditionally, its use in infants is not recommended due to concerns about adverse effects of fluoroquinolones on the developing joints of infants. However, recent studies suggest the risk is minimal. Calcium in breast milk may prevent the absorption of small amounts of fluoroquinolones in breast milk, but there is currently insufficient data to confirm or refute this claim. Lactating women can use lomefloxacin, but close monitoring of the infant's gut microbiota is necessary, for example, for changes in diarrhea or candidiasis (thrush, diaper rash). However, it is best to use alternative medications with available safety information.
◉ 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
10%
Lomefloxacin is generally well-tolerated. Common side effects include gastrointestinal disturbances and photosensitivity. It is contraindicated in patients with a history of tendon disorders. It is a prescription medication.

:J Chromatogr B Analyt Technol Biomed Life Sci. 2010 Oct15;878(28):2937-41;Pak J Pharm Sci. 2005Jul;18(3):59-65.

Lomefloxacin is a fluoroquinolone antibiotic, commonly used in its hydrochloride form to treat bacterial infections, including bronchitis and urinary tract infections (UTIs). It is also used for preoperative prophylaxis of UTIs. It has antibacterial, photosensitizing, and antituberculosis effects. It is a quinolone, N-arylpiperazine, quinoline monocarboxylic acid, quinolone antibiotic, and fluoroquinolone antibiotic. Lomefloxacin is a fluoroquinolone antibiotic used to treat bacterial infections, including bronchitis and UTIs. It is also used for preoperative prophylaxis of UTIs. Lomefloxacin is a synthetic broad-spectrum fluoroquinolone antibacterial drug. Lomefloxacin inhibits DNA gyrase, a type II topoisomerase involved in the induction or relaxation of supercoiling during DNA replication. This inhibition leads to reduced DNA synthesis during bacterial replication, thereby inhibiting cell growth and ultimately causing cell lysis. Drug Indications Lomefloxacin is used to treat bacterial infections of the respiratory tract (chronic bronchitis) and urinary tract, and as a preoperative prophylactic agent to prevent urinary tract infections caused by the following bacteria: Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Pseudomonas aeruginosa, Enterobacter cloacae, Proteus mirabilis, Pseudomonas viride, Staphylococcus saprophyticus, Escherichia coli, and Klebsiella pneumoniae. FDA Label Mechanism of Action Lomefloxacin is a bactericidal fluoroquinolone drug active against a variety of Gram-negative and Gram-positive bacteria. The bactericidal action of lomefloxacin derives from its interference with the activity of bacterial DNA gyrase and topoisomerase IV, both of which are essential for bacterial DNA transcription and replication. DNA gyrase appears to be the primary target of quinolones against Gram-negative bacteria. Topoisomerase IV appears to be the preferred target for Gram-positive bacteria. Interference with these two topoisomerases leads to bacterial chromosome strand breaks, supercoiling, and rejoining. Therefore, DNA replication and transcription are suppressed. Lomefloxacin is a fluoroquinolone antibiotic used to treat chronic bronchitis and complicated and uncomplicated urinary tract infections. It can also be used as a prophylactic treatment to prevent urinary tract infections in patients undergoing transrectal or transurethral surgery. Fluoroquinolones, such as lomefloxacin, have excellent antibacterial activity against Gram-negative aerobic bacteria (such as Escherichia coli and Neisseria gonorrhoeae) and Gram-positive bacteria (including Streptococcus pneumoniae and Staphylococcus aureus). They also have effective antibacterial activity against Shigella, Salmonella, Campylobacter, Neisseria gonorrhoeae, and multidrug-resistant Pseudomonas and Enterobacteriaceae.
Lomefloxacin is a clinically used antibiotic for the treatment of bacterial infections. It is available as a generic medication. It is not typically used as a research compound.

C₁₇H₁₉F₂N₃O₃

351.35

351.139

98079-51-7

Lomefloxacin hydrochloride;98079-52-8;Lomefloxacin (aspartate);211690-33-4

3948

Typically exists as solid at room temperature

1.3±0.1 g/cm3

542.7±50.0 °C at 760 mmHg

239-240ºC

282.0±30.1 °C

0.0±1.5 mmHg at 25°C

1.566

1.71

2

8

3

25

586

0

O=C(C1=CN(CC)C2=C(C=C(F)C(N3CC(C)NCC3)=C2F)C1=O)O

ZEKZLJVOYLTDKK-UHFFFAOYSA-N

InChI=1S/C17H19F2N3O3/c1-3-21-8-11(17(24)25)16(23)10-6-12(18)15(13(19)14(10)21)22-5-4-20-9(2)7-22/h6,8-9,20H,3-5,7H2,1-2H3,(H,24,25)

1-ethyl-6,8-difluoro-7-(3-methylpiperazin-1-yl)-4-oxoquinoline-3-carboxylic acid

DM-10CCRIS-6305DM10CCRIS6305

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.)