Understanding Fluoroquinolones and their Uses

Sep 16, 2024

Lecture Notes: Fluoroquinolones

Overview

  • Fluoroquinolones: Also known as quinolones, are antibiotics effective against both gram-negative and gram-positive bacteria.

Gram-Negative Bacteria Targeted

  • Hemophilus influenzae: Causes epiglottitis and respiratory infections.
  • Neisseria gonorrhea: Causes gonorrhea.
  • Chlamydia
  • E. coli
  • Klebsiella pneumoniae
  • Salmonella
  • Pseudomonas aeraginosa

Gram-Positive Bacteria Targeted

  • Streptococcus pneumoniae: Especially by newer quinolones.
  • Enterococcus
  • Staphylococcus aureus

Infections Treated

  • Urinary tract infections
  • Skin infections
  • Respiratory infections
  • Sexually transmitted infections
  • Abdominal, joint, and bone infections

Administration

  • Typically administered orally due to good absorption in the gut.
  • Can also be given parenterally if needed.

Identification

  • Look for the suffix "floxacin" in the generic name to identify a fluoroquinolone.
  • Examples include:
    • Ofloxacin, Norfloxacin, Ciprofloxacin, Gemifloxacin, Levofloxacin, Moxifloxacin, and Delafloxacin.

Mechanism of Action

  • Fluoroquinolones have a bactericidal effect, killing bacteria.
  • They inhibit bacterial DNA replication by targeting two enzymes:
    • DNA Gyrase
    • Topoisomerase IV

DNA Replication Disruption

  • Gram-Negative: Targets DNA gyrase to disrupt supercoiling.
  • Gram-Positive: Inhibits topoisomerase IV, preventing daughter DNA strand separation.

Nurse's Role

  • Check for patient allergies before administration.
  • Assess effectiveness of the medication.
    • Monitor temperature, white blood cell count, and vital signs for symptoms of infection or septic shock.

Patient Education and Monitoring

  • Fluid Intake: Prevent crystaluria, especially with ciprofloxacin. Ensure at least 2 liters of fluid daily.
  • Long QT Interval: Monitor ECG for QT interval prolongation.
  • Older Adults: Risk of tendon inflammation or rupture, especially with Achilles tendon.
  • Cation Interactions: Avoid antacids, vitamins, and dairy products around administration times.
  • Children and Pregnancy: Avoid use due to risk of bone and cartilage problems.
  • C. diff Monitoring: Watch for symptoms of superinfection in the gut.
  • Drug Interactions: Be cautious with caffeine, phenytoin, warfarin, theophylline, and amiodarone.
  • Neuromuscular Exacerbation: Monitor patients with myasthenia gravis.
  • Sun Sensitivity: Educate on skin protection from sunlight.

Note: Use the free quiz provided in the video description to test your knowledge on fluoroquinolones.