Disposition of levetiracetam in healthy adult horses.

This research investigates the effects of administering the drug Levetiracetam in different methods (intravenous and intragastric) to nine healthy adult horses. The study found single doses of the drug to be well-tolerated and proposed a dosage regimen that maintains therapeutic ranges similar to those suggested for humans.

Research Methodology

• The research involved giving nine horses doses of Levetiracetam (LEV) configured in three distinct ways in a randomized crossover design. The types of dosage were intravenous (LEV ), intragastric with immediate-release (LEV ), and intragastric with extended release (LEV ). Each horse received 20 mg/kg of intravenous and 30 mg/kg of intragastric Levetiracetam.
• The crushed tablet forms were mixed with water and given via a nasogastric tube.
• Over a 48 hour period, serum samples from the horses were collected at specific intervals for comprehensive analysis.

Data Analysis and Findings

• Levetiracetam concentrations in the serum samples were evaluated using immunoassay techniques.
• Peak concentration averages for LEV and LEV were 50.72 ± 10.60 and 53.58 ± 15.94 μg/ml, respectively, while IV administration’s y-intercept was 64.54 ± 24.99 μg/ml.
• The study also estimated the terminal half-life of the different forms of LEV, which varied between 6.22 – 7.07 hours, and noted a volume of distribution at steady-state of 630 ± 73.4 ml/kg.
• Body clearance and bioavailability were also calculated; the former was 74.40 ± 19.20 ml kg hr after IV administration, whereas bioavailability was around 96% for LEV and 98% for LEV , thus showing that the drug was efficiently absorbed in both the immediate and extended-release forms.

Conclusions and Suggestions

• A single dose of Levetiracetam, irrespective of its form, was found to be well-tolerated by the horses in the study.
• The data suggested a possible dosing regimen of either intravenous or oral LEV at 32 mg/kg, to be administered every 12 hours, in order to attain and sustain therapeutic plasma levels in adult horses.
• These levels are within the therapeutic range advised for humans and offer optimal kinetics throughout the dosing period.
• The research calls for further investigations with repeated dosing and pharmacodynamic studies to extend this initial study’s findings and recommendations.