Fluorokinoloner

Fluorokinoloner, known in English as fluoroquinolones, is a class of broad‑spectrum synthetic antibiotics that inhibit bacterial DNA gyrase and topoisomerase IV, enzymes essential for DNA replication. This inhibition leads to bactericidal activity against a wide range of pathogens.

Introduced in the 1980s, the class includes agents such as ciprofloxacin, levofloxacin, moxifloxacin, norfloxacin, ofloxacin, and gemifloxacin. They have varying activity against Gram‑negative bacteria, Gram‑positive cocci, and atypical pathogens. Earlier generations provided strong Gram‑negative coverage (notably Pseudomonas with ciprofloxacin), while later generations improved Gram‑positive and atypical activity. Resistance commonly arises through mutations in gyrA/gyrB and parC, and through plasmid‑mediated qnr genes and efflux pumps.

Fluorokinoloner are available for oral and intravenous use, with generally good tissue and intracellular penetration. They are used for a variety of infections, including complicated urinary tract infections, other urinary tract infections, gynecologic infections, intra‑abdominal infections, community‑ and hospital‑acquired pneumonia, and skin and soft tissue infections. Some agents have strong activity against anaerobes (e.g., moxifloxacin) but limited urinary excretion, affecting their use in UTIs. They have also been used for certain exposures to Bacillus anthracis (anthrax) in specific scenarios.

Safety and stewardship are important considerations. Adverse effects range from common GI upset and headache to serious events such as tendinopathy and tendon rupture, peripheral neuropathy, CNS effects, and QT interval prolongation. They should be avoided in pregnancy and in children unless indications justify use; caution is advised in the elderly and in those on QT‑prolonging drugs. Drug interactions include chelation with divalent cations and antacids, which can reduce absorption. Responsible use is encouraged to limit resistance development.