The comparative pharmacokinetics of five quinolones

Area of Science:

• Pharmacology
• Clinical Pharmacy
• Infectious Diseases

Background:

• Quinolone antibiotics are crucial in treating bacterial infections.
• Understanding their pharmacokinetic profiles is essential for optimizing therapeutic efficacy.
• Variations in absorption, distribution, metabolism, and excretion impact clinical outcomes.

Purpose of the Study:

• To evaluate and compare the pharmacokinetics and tissue penetration of five quinolone agents.
• To determine absorption rates, serum concentrations, half-lives, and urinary excretion of selected quinolones.
• To assess the clinical relevance of these pharmacokinetic parameters in volunteer subjects.

Main Methods:

• Volunteer study administering five quinolones: norfloxacin, enoxacin, ciprofloxacin, ofloxacin, and pefloxacin via oral (po) or intravenous (iv) routes.
• Measurement of pharmacokinetic parameters including time to maximum concentration (Tmax), serum half-life, and 24-hour urine recovery.
• Assessment of drug penetration into blister fluid.

Main Results:

• Ofloxacin and ciprofloxacin exhibited the fastest oral absorption (Tmax = 1.2 h).
• Ofloxacin achieved the highest serum levels, while pefloxacin had the longest serum half-life (10.5 h).
• All quinolones demonstrated good penetration into blister fluid, with significant variations in 24-hour urine recovery.

Conclusions:

• Significant pharmacokinetic differences exist among the studied quinolone antibiotics.
• Ofloxacin and ciprofloxacin present favorable absorption and serum concentration profiles.
• These findings aid in selecting appropriate quinolones based on desired pharmacokinetic and tissue penetration characteristics.