Title: Ciprofloxacin
CAS Registry Number: 85721-33-1
CAS Name: 1-Cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinolinecarboxylic acid
Manufacturers' Codes: Bay q 3939
Molecular Formula: C17H18FN3O3
Molecular Weight: 331.34
Percent Composition: C 61.62%, H 5.48%, F 5.73%, N 12.68%, O 14.49%
Literature References: Fluorinated quinolone antibacterial. Prepn: K. Grohe et al., DE 3142854; eidem, US 4670444 (1983, 1987 both to Bayer AG); K. Grohe, H. Heitzer, Ann. 1987, 29. Antibacterial spectrum in vitro: B. Watt, F. V. Brown, J. Antimicrob. Chemother. 17, 605 (1986); C. M. Bassey et al., ibid. 623. HPLC determn in biological fluids: W. Gau et al., J. Liq. Chromatogr. 8, 485 (1985). Pharmacokinetics: G. Hoffken et al., Antimicrob. Agents Chemother. 27, 375 (1985). Clinical trials: C. A. Ramirez et al., ibid. 28, 128 (1985); B. E. Scully et al., Lancet 1, 819 (1986). Symposia on antibacterial spectrum and clinical use: Am. J. Med. 82, Suppl. 4A, 1-404 (1987); J. Antimicrob. Chemother. 26, Suppl. F, 3-193 (1990). Review of clinical safety and efficacy in children: R. Kubin, Infection 21, 413-421 (1993).
Properties: Dec 255-257°.
Derivative Type: Monohydrochloride monohydrate
CAS Registry Number: 86393-32-0
Manufacturers' Codes: Bay o 9867
Trademarks: Baycip (Bayer); Ciflox (Bayer); Ciloxan (Alcon); Cipro (Bayer); Ciprobay (Bayer); Ciproxan (Bayer); Ciproxin (Bayer); Flociprin (IBI); Septicide (Bago); Uniflox (Bayer); Velmonit (Esteve)
Molecular Formula: C17H18FN3O3.HCl.H2O
Molecular Weight: 385.82
Percent Composition: C 52.92%, H 5.49%, F 4.92%, N 10.89%, O 16.59%, Cl 9.19%
Properties: Light yellow crystalline powder. mp 318-320°.
Melting point: mp 318-320°
Therap-Cat: Antibacterial.
Keywords: Antibacterial (Synthetic); Quinolones and Analogs.
Ciramadol Circulins Cisapride Cisplatin Citiolone

Systematic (IUPAC) name
1-cyclopropyl-6-fluoro-4-oxo-7-(piperazin-1-yl)-quinoline-3-carboxylic acid
Clinical data
Trade names Ciloxan, Cipro, Neofloxin
AHFS/ monograph
MedlinePlus a688016
Licence data US FDA:link
Pregnancy cat. B3 (AU) C (US)
Legal status Prescription Only (S4) (AU) POM (UK) -only (US)
Routes Oral, intravenous, topical (ear drops, eye drops)
Pharmacokinetic data
Bioavailability 69%[1]
Metabolism Hepatic, including CYP1A2
Half-life 4 hours
Excretion Renal
CAS number 85721-33-1 YesY
ATC code J01MA02 S01AE03 S02AA15 S03AA07
PubChem CID 2764
DrugBank DB00537
ChemSpider 2662 YesY
KEGG D00186 YesY
ChEBI CHEBI:100241 YesY
NIAID ChemDB 001992
Chemical data
Formula C17H18FN3O3 
Mol. mass 331.346 g/mol
 YesY (what is this?)  (verify)
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Ciprofloxacin (INN) is a second-generation fluoroquinolone antibiotic.[2][3] Its spectrum of activity includes most strains of bacterial pathogens responsible for respiratory, urinary tract, gastrointestinal, and abdominal infections, including Gram-negative (Escherichia coli, Haemophilus influenzae, Klebsiella pneumoniae, Legionella pneumophila, Moraxella catarrhalis, Proteus mirabilis, and Pseudomonas aeruginosa), and Gram-positive (methicillin-sensitive but not methicillin-resistant Staphylococcus aureus, Streptococcus pneumoniae, Staphylococcus epidermidis, Enterococcus faecalis, and Streptococcus pyogenes) bacterial pathogens. Ciprofloxacin and other fluoroquinolones are valued for this broad spectrum of activity, excellent tissue penetration, and for their availability in both oral and intravenous formulations.[4]

Ciprofloxacin is used alone or in combination with other antibacterial drugs in the empiric treatment of infections for which the bacterial pathogen has not been identified, including urinary tract infections[5][6] and abdominal infections[7] among others. It is also used for the treatment of infections caused by specific pathogens known to be sensitive.

Ciprofloxacin is the most widely used of the second generation quinolone antibiotics that came into clinical use in the late 1980s and early 1990s.[8][9] In 2010 over 20 million outpatient prescriptions were written for ciprofloxacin, making it the 35th most commonly prescribed drug, and the 5th most commonly prescribed antibacterial, in the US.[10] Ciprofloxacin was first patented in 1983 by Bayer A.G. and subsequently approved by the US Food and Drug Administration (FDA) in 1987. Ciprofloxacin has 12 FDA-approved human uses and other veterinary uses, but it is often used for unapproved uses (off-label).

Overall, the safety of ciprofloxacin and other fluoroquinolones appears to be similar to that of other antibiotics, but serious side effects occur on occasion. There is some disagreement in the literature regarding whether fluoroquinolones produce serious adverse events at a higher rate than other broad-spectrum antibiotics.[11][12][13][14][15] The U.S. FDA-approved label for ciprofloxacin includes a "black box" warning of increased risk of tendon damage and/or rupture and for exacerbation of muscle weakness in patients with the neurological disorder myasthenia gravis.[16]