Pharmacokinetics of difloxacin after intravenous, intramuscular, and intragastric administration to horses.

This research study evaluates the effect of different administration routes (intravenous, intramuscular, and intragastric) on the pharmacokinetics of difloxacin in healthy horses. The study shows that the medication may be effective for treating bacterial infections in horses.

Research Methodology

• The researchers employed a crossover study design which included three phases, with long washout periods of 15 days between different treatments.
• The subjects of the study comprised of six healthy mature horses. These horses were administered a 5% difloxacin formulation intravenously and intramuscularly in a single dose, whereas for the intragastric method, an oral solution was prepared and given through a nasogastric tube.
• Blood samples were systematically collected before and at consistent intervals after each administration to monitor the concentration of difloxacin in the blood plasma.
• A high-performance liquid chromatography assay with fluorescence detection was employed to determine these plasma difloxacin concentrations.

Findings

• The findings suggest that the time-concentration data for difloxacin plasma following an intravenous administration can better be described by a 2-compartment open model, while a 1-compartment model was sufficient to describe the disposition of difloxacin after intramuscular or intragastric administration.
• It was also found that the average half-life of difloxacin after being administered via intravenous, intramuscular, and intragastric routes was 2.66, 5.72, and 10.75 hours respectively.
• The report further detailed that the clearance rate post an IV administration was 0.28 L/kg.h. The absolute mean bioavailability after intramuscular and intragastric administration was 95.81 +/- 3.11% and 68.62 +/- 10.60%, respectively.
• A significant finding from the study was that the plasma creatine kinase activity had risen seven-fold 12 hours after intramuscular administration in comparison to the pre-injection levels, indicating possible tissue damage.

Conclusion

• The research concluded that the findings point to the likelihood of difloxacin being effective in treating susceptible bacterial infections in horses.