Ciflo Mechanism of Action

Pharmacology: 250 mg: Ciprofloxacin belongs to the fluoroquinolone class of antibiotics. It exhibits broad-spectrum antibacterial activity by inhibiting bacterial DNA gyrase and topoisomerase IV, enzymes essential for bacterial DNA replication, transcription, repair, and recombination. This mechanism disrupts bacterial cell division, ultimately leading to cell death. Even though they are resistant to other antibiotics that are not in the quinoline carboxylic acid derivatives, such as aminoglycosides, penicillins, cephalosporins and tetracyclines.
Ciprofloxacin is active against a wide range of gram-positive and gram-negative pathogens including Escherichia coli (E. coli), Neisseria gonorrhoeae, Klebsiella pneumoniae, Salmonella, Shigella, and others.
Ciprofloxacin demonstrates efficacy against resistant bacterial strains such as E. coli, Klebsiella, Enterobacter, Pseudomonas aeruginosa, Staphylococcus aureus (including methicillin-resistant Staphylococcus aureus, MRSA), and others. It is also effective against organisms like Haemophilus influenzae, Moraxella catarrhalis, Proteus mirabilis, and Bacteroides fragilis. This agent acts against gram-negative bacteria such as Salmonella typhi, Yersinia pestis, Vibrio cholerae, and gram-positive bacteria like Staphylococcus aureus and Streptococcus pneumoniae.
Ciprofloxacin is rapidly absorbed following oral administration, with peak plasma concentrations typically achieved within 60-90 minutes. Approximately 70-80% of the drug is bioavailable, and high concentrations are achieved in tissues and fluids, making it effective for treating a variety of systemic infections.
500 mg: Mechanism of action: Ciprofloxacin is a broad-spectrum fluoroquinolones antimicrobial that kills a wide range of gram-negative and some gram-positive bacteria by inhibiting the enzyme DNA gyrase, which is essential for bacterial DNA synthesis, repair, and transcription.
Quinolone drugs have a similar mechanism of action, so bacteria that are resistant to one quinolone will also be resistant to other quinolone drugs.
Scope of action against microorganisms: Ciprofloxacin has a broad spectrum of action and is active against both gram-positive and gram-negative aerobic bacteria. Anaerobic bacteria are often resistant to this drug.
Gram-negative organisms are susceptible to this drug include Enterobacteriaceae such as Citrobacter sp., Enterobacter sp., Escherichia coli, Klebsiella sp., Morganella morganii, Proteus sp. (P. mirabilis and P. vulgaris), Salmonella sp., Shigella sp., Vibrio sp., and Yersinia enterocolitica. This drug is active against other drug-resistant gram-negative rods such as penicillin-resistant Neisseria gonorrhoeae, beta-lactamase-produced by Haemophilus influenzae, and Moraxella catarrhalis. Normally, this drug does not kill Pseudomonas such as Ps. maltophila and Ps. cepacia, but it is very active against to Ps. aeruginosa.
Gram-positive organisms are susceptible to this drug including Staphylococci such as S. aureus, S. saprophyticus, and S. epidermidis. But Streptococci such as S. pneumoniae, S. pyogenes, and Enterococcus faecalis are moderately susceptible to this drug, like Ofloxacin, and should not be used as first-line therapy for pneumococcal pneumoniae.
The drug is also active against Chlamydia trachomatis, Mycoplasma sp., Legionella sp., Mycobacterium tuberculosis and atypical mycobacteria.
Pharmacokinetics: Ciprofloxacin is well absorbed from the gastrointestinal tract (50-84%). Food slows the absorption of ciprofloxacin from the gastrointestinal tract. Antacids, medications containing calcium, iron, and zinc reduce the absorption of ciprofloxacin. Ciprofloxacin levels are highest in the blood after drug is administered orally for 60-75 minutes. If a dose of 500 mg is administered orally, the maximum drug level is 2.5 mg/L. The drug is distributed throughout the body with a Vd of 2-3.5 L/kg, but in the elderly (64-91 years), the Vd is higher to 3.5-3.6 L/kg. Under normal conditions, the drug enters the cerebrospinal fluid very little. The drug level in the cerebrospinal fluid is only 6-10% of the blood level. However, if there is inflammation of the meninges, the drug can enter the brain more and the drug level is high enough to kill the disease. The drug is bound to plasma proteins by 20-40%, a half-life of 3-4 hours in normal people, but is longer in patients with kidney disease. The drug is metabolized in the liver and enters the enterohepatic circulation. Therefore, the drug is found in the feces in both the original form (20-40%) and metabolites (10-15%). These substances still have antibacterial activity. The remaining 15-50% is excreted in the urine in the original form. Most of the drug is excreted in the urine by tubular secretion, so co-administration with probenecid will increase drug levels and half-life. The drug crosses the placenta and is also excreted in breast milk. The drug is eliminated only slightly by hemodialysis or peritoneal dialysis.