Ciprofloxaxin is associated with which antibiotic class?

• A. Penicillin
• B. Macrolides
• C. Cephalosporin
• D. Quinolones

Answer: (D)

Ciprofloxacin belongs to the quinolone class, specifically the fluoroquinolones. This group works by inhibiting bacterial DNA replication enzymes—DNA gyrase and topoisomerase IV—leading to disrupted DNA synthesis and bacterial death. That mechanism is different from penicillins and cephalosporins, which block cell wall synthesis (beta‑lactam action), and from macrolides, which inhibit protein synthesis by targeting the 50S ribosomal subunit. The fluorinated structure of ciprofloxacin defines the fluoroquinolone subset, highlighting its role as a DNA synthesis–targeting antibiotic rather than a cell wall– or protein synthesis–inhibiting agent.