Antibiotics - Fluoroquinolones: Nursing pharmacology

Fluoroquinolones are a group of broad spectrum antibiotics, which can be used to treat a wide variety of bacterial infections. These include eye infections like bacterial conjunctivitis; chest infections like Tuberculosis or pneumonia; gastrointestinal infections like shigellosis; urinary tract infections or UTIs; genital infections like gonorrhea; and bone and joint infections.

They are very effective against several gram negative organisms like Enterobacteriaceae spp., Haemophilus spp., Legionella spp., Neisseria spp., Moraxella spp., and even Pseudomonas spp. and gram positive bacteria like Streptococcus pneumoniae.

Now, there are four generations of fluoroquinolones, but among all of them only a few are commonly used. They are ciprofloxacin, levofloxacin, moxifloxacin, norfloxacin and ofloxacin. These medications can be administered both orally or intravenously, while ciprofloxacin and ofloxacin are also available in otic formulations, and ofloxacin and moxifloxacin are available as ophthalmic solutions.

Once administered, fluoroquinolones have a bactericidal effect by inhibiting a bacterial enzyme called DNA topoisomerase, also known as DNA gyrase, which is essential for bacteria to loosen up the tight coilings of DNA for the replication process. As a result, when DNA gyrase is inhibited by fluoroquinolones, bacterial DNA replication comes to a halt, ultimately killing the bacteria.

However, fluoroquinolones may cause side effects like central nervous system disturbances, including headache and restlessness, as well as dizziness, confusion, depression, nightmares, insomnia, and some may even present with seizures.