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Systematic (IUPAC) name
1-ethyl-6-fluoro-7- (4-methylpiperazin-1-yl)- 4-oxo-quinoline-3-carboxylic acid
CAS number 70458-92-3
ATC code J01MA03
PubChem 51081
DrugBank APRD00108
Chemical data
Formula C17H20FN3O3 
Mol. mass 333.358 g/mol
Pharmacokinetic data
Bioavailability 100%
Protein binding 20–30%
Metabolism Hepatic
Half life 8.6 hours
Excretion Mostly renal, also biliary
Therapeutic considerations
Pregnancy cat.


Legal status
Routes  ?

Pefloxacin is an antimicrobial agent. It is a synthetic fluoroquinolone, belonging to the 3rd generation of quinolones.


Mode of Action

  • Chromosomal DNA in bacterial cells occurs mainly in the form of a double stand ring.
  • One of a group of bacterial enzymes- DNA gyrase is responsible for the supercoiling process.
  • Pefloxacin bactericidal affect is due to its ability to inhibit the activity of this vital enzyme.
  • The result of this inhibitions is the prevention of bacterial DNA replication.
  • Although inhibition of DNA replication is undoubtedly the chief means by which Abaktal exerts its antibacterial effect, two other actions are also observed:
    • Pefloxacin reduces the ability of E-coli and staphylococcus to adhere to the walls of uroephithelial cells.
    • Pefloxacin has effects on the immune system, stimulating the phagocytic activity of white blood.

Spectrum of antibacterial activity

  • Extensive in vitro & in vivo testing has established that Abaktal has a broad antibacterial spectrum.
  • The MICs of Pefloxacin even against bacteria resistant to beta-lactams and aminoglycosides are very low
  • Initial plasma level of 4.0 mcg/ml, well above M.I.C. for sensitive pathogens, are ready and rapidly attained after a single 400mg dose (oral or i.v.)
  • Excellent tissue penetration level is achieved with Pefloxacin in human and animals studies
  • Species usually sensitive (MIC < 1pg/ml)are Escherichia coli, Klebsiella, Enterobacter, Serratia, Proteus mirabilis, Proteus vulgaris, Citrobacter, Salmonella, Shigella, Haemophilus influenzae, Staphylococcus aureus, and Neisseria gonorrhoeae.
  • Species variably sensitive include Streptococcus and Pneumococcus, Pseudomonas aeruginosa, Acinetobacter, Clostridium perfringens, Mycoplasma, and Chlamydia.


  • After oral administration, Abaktal is well absorbed; the bio availability is 100%.
  • Peak plasma levels is reached in 1-1.5 hours
  • Peak serum levels of 3.8-6.6mcg/ml is attained after single dose of 400mg
  • Peak serum levels after multiple dose of 400mg, 12 hourly is 8-10 mcg/ml
  • Steady state concentration is achieved
  • Dose depended increase in plasma level over the dose of 200- 800mg
  • Food slows the absorption but does not effects bio availability
  • Oral & injectable forms are bio-equivalent
  • Elimination half life is 11-12 hours mainly through metabolites
  • Pefloxacin is metabolized in liver (85%-90%)
  • Plasma protein binding is 20-30%
  • Major route of elimination is renal – 9-16% of the drugs is eliminated unchanged
  • Major metabolites constitute up to 84% of drugs recovered in urine
  • Limited excretion via bile
  • N-dismethyl pefloxacin (norfloxacin) activity unknown
  • Pefloxacin N-oxide active
  • Oxodimethyl activity unknown
  • Oxo pefloxacin activity unknown
  • Pefloxacin achieves high tissue concentration

Tissue Concentration Bronchial tissues 5 mcg/ml Oropharyngeal concentration 6 mcg/ml Tonsils 9 mcg/ml Maxillary sinus cavity sinus 2.82 mcg/ml, 4.1 mcg/ml, 2-8mcg/ml aspirate sinus cystic fluid nasal secretions Muscles 5.6 mcg /ml Gall bladder 80 mcg /ml Bile 78 mcg /ml Kidney 90 mcg /ml Prostate 10 mcg /ml Gynecological tissue 38 mcg/ml 4-6 higher than serum conc., Myometrium- 38.6 mcg /ml, Fallopian tube 31.9 mcg /ml, Ovaries 44.8mcg/ml Pancreatic tissue 4.6mcg/ml Peritonium 3.5mcg/ml

  • There are no major change in plasma pharmacokinetics as a function of renal impairment
  • Elimination half life increase slightly to approx.15 hours
  • There is a fall in urinary excretion of Abaktal & its metabolites
  • There is no major change in Abaktal plasma levels whatever the degrees of renal impairment
  • Pefloxacin is not readily dialyzed
  • There are marked changes in pharmacokinetics in patients with hepatic impairment
  • Marked increase in :
    • Elimination half life 3-5 times
    • Area under curve 3-6 times
    • Urinary excretion of unchanged Abaktal 3-4 times
  • Careful monitoring of plasma levels together with appropriate dosage adjustment will be necessary


Indicated for the following conditions:

  • Respiratory infections
  • Ear, nose and throat infections
  • Renal and urinary infections
  • Gynaecological infection
  • Abdominal and hepato-biliary infections
  • Bone and joint infections
  • Skin and soft tissue infection
  • Septicaemia and endocarditis


  • Children or adolescents
  • Pregnant women
  • Nursing mothers
  • History of hypersensitivity to quinolones
  • Patients with a history of tendon lesion tendinitis or tendon rupture

Precaution & side effects


  • Hepatic dysfunction
  • Avoid exposure to sunlight during treatment

Side effects

  • Nausea
  • Skin rash
  • Photo sensitivity reaction
  • Insomnia
  • Headache
  • Myalgia
  • Thrombo-cytopenia

Drug comparisons

Pefloxacin vs. Ciprofloxacin

Pefloxacin 400mg oral Ciprofloxacin 500mg oral
Bioavailability 100% 50-70%
Peak plasma conc.(mcg/ml) 8-10 2.3-2.7
Trough 4-5 0.3-0.4
Plasma half life (hours) 11-12 4-5

Pefloxacin vs. Norfloxacin

Pefloxacin 400mg oral Norfloxacin 400mg oral
Absorption 100% 30-40%
Peak plasma conc.(mcg/ml) 4-5 1.4-1.6
Plasma protein binding 30% 15%
Plasma half life (hours) 11-12 3-4
Urinary Excretion 60% 30-50%

Dosage & Presentation

Oral Tablets: 400mg Twice daily

Injection: Administer by slow I.V. at a dosage of 400mg diluted in 100 or 250 ml of 5% isotonic solution (Over a period of 1 hr) Twice daily

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Pefloxacin". A list of authors is available in Wikipedia.
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