Ciprofloxacin
[CAS# 85721-33-1]

Identification

• Classification: API >> Synthetic anti-infective drugs >> Quinolone
• Name: Ciprofloxacin
• Synonyms: 1-Cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinolinecarboxylic acid
• Molecular Formula: C₁₇H₁₈FN₃O₃
• Molecular Weight: 331.34
• CAS Registry Number: 85721-33-1
• EC Number: 617-751-0
• SMILES: C1CC1N2C=C(C(=O)C3=CC(=C(C=C32)N4CCNCC4)F)C(=O)O

Safety Data

• Hazard Symbols: GHS07;GHS09 Warning
• Risk Statements: H319-H410-H412
• Safety Statements: P264+P265-P273-P280-P305+P351+P338-P337+P317-P391-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Eye irritation	Eye Irrit.	2	H319
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Specific target organ toxicity - single exposure	STOT SE	3	H335
Skin irritation	Skin Irrit.	2	H315
Respiratory sensitization	Resp. Sens.	1	H334
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Eye irritation	Eye Irrit.	2A	H319
Skin sensitization	Skin Sens.	1	H317
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411

Discovery and Applications

Ciprofloxacin is a widely used antibiotic belonging to the fluoroquinolone class, known for its broad-spectrum antibacterial activity. It was discovered in the early 1980s by Bayer AG, a German pharmaceutical company, as part of a broader effort to develop more potent antibiotics to combat a wide range of bacterial infections. Ciprofloxacin quickly became one of the most important antibiotics due to its efficacy, safety profile, and versatility in treating various infections.

Ciprofloxacin works by inhibiting bacterial DNA gyrase and topoisomerase IV, enzymes essential for bacterial DNA replication, transcription, and repair. By disrupting these processes, ciprofloxacin prevents bacteria from multiplying, leading to their eventual death. This mechanism of action allows ciprofloxacin to be effective against a wide variety of Gram-negative and Gram-positive bacteria, making it suitable for treating infections in different parts of the body.

The approval of ciprofloxacin by the U.S. Food and Drug Administration (FDA) in 1987 marked a significant milestone in antibiotic therapy. Its ability to treat infections that were resistant to other antibiotics quickly made it a valuable tool in the medical arsenal. Ciprofloxacin is particularly effective against urinary tract infections (UTIs), respiratory tract infections, skin infections, gastrointestinal infections, and certain sexually transmitted infections.

One of the key advantages of ciprofloxacin is its oral bioavailability, which allows it to be administered both orally and intravenously. This flexibility makes it easier to transition patients from hospital to outpatient care, reducing the need for prolonged hospital stays. Ciprofloxacin is also available in ophthalmic and otic formulations, making it a versatile option for treating infections of the eyes and ears.

Ciprofloxacin's broad spectrum of activity has made it a go-to antibiotic in many clinical settings. It is commonly prescribed for UTIs, including those caused by drug-resistant bacteria, and for respiratory infections such as pneumonia and bronchitis. Additionally, ciprofloxacin is used to treat gastrointestinal infections like infectious diarrhea and typhoid fever, as well as skin infections caused by susceptible bacteria. It is also one of the few oral antibiotics that can effectively treat Pseudomonas aeruginosa, a particularly challenging pathogen.

However, the widespread use of ciprofloxacin has led to concerns about antibiotic resistance. Over time, certain bacteria have developed mechanisms to resist the effects of ciprofloxacin, limiting its effectiveness in some cases. As a result, healthcare providers are encouraged to use ciprofloxacin judiciously, reserving it for infections where it is most likely to be effective and avoiding its use in cases where other antibiotics would suffice.

Ciprofloxacin is generally well-tolerated, but like all medications, it can cause side effects. Common side effects include gastrointestinal disturbances such as nausea, diarrhea, and abdominal pain. More serious side effects, though rare, include tendonitis and tendon rupture, particularly in older adults, as well as potential effects on the central nervous system, such as dizziness and confusion. Due to these risks, the use of ciprofloxacin is often avoided in certain populations, such as pregnant women and children, unless absolutely necessary.

Despite these concerns, ciprofloxacin remains an essential antibiotic in modern medicine. Its discovery and subsequent development have significantly impacted the treatment of bacterial infections, providing a reliable option for many common and severe infections. Ongoing research and careful clinical use aim to preserve the effectiveness of ciprofloxacin and other fluoroquinolones in the face of rising antibiotic resistance.

References

1899. Studien über saure Milch und Zähmilch. Zeitschrift für Hygiene und Infektionskrankheiten, 29(1).
DOI: 10.1007/bf02206645

1895. Das Verhältniss von Dextrose zu Lävulose im Süsswein und Honig und die Benutzung desselben zum Nachweis von Verfälschungen dieser Genussmittel. Zeitschrift für analytische Chemie, 34(1).
DOI: 10.1007/bf01595718