Pharmacokinetics and pharmacodynamics of meldonium in exercised thoroughbred horses.

This research set out to examine the effects of meldonium on exercised thoroughbred horses, given its widespread misuse in human sports and potential use in equine athletics. Data indicates that the medication has a prolonged detection time in biological samples from horses and impacts glucose concentrations but has no adverse effects.

Study Design and Methodology

• The research was based on a study of eight adult thoroughbred horses who were subjected to exercise.
• Each horse was given a single dosage of meldonium ranging from 3.5 to 21.4 mg/kg.
• Blood and urine samples were collected from the horses for analysis using liquid chromatography tandem mass spectrometry.
• Pharmacokinetic parameters of meldonium in the horses were determined using non-compartmental analysis.

Results of the Study

• The study observed that maximum serum concentrations of meldonium ranged from 440.2 to 1147 ng/mL while meldonium’s elimination half-life ranged from 422 hours to 647.8 hours.
• It was determined that serum concentrations fell below the limit of quantitation by days 4, 7, 12, and 12 corresponding to dosages of 3.5, 7.1, 14.3, and 21.4 mg/kg respectively.
• Urine concentrations of the substance were found to be below the limit of detection by the 44th day after administration of the lowest dosage (3.5 mg/kg) and by the 51st day for all other dosages.
• Remarkably, the study found no adverse effects in horses following the administration of meldonium.
• Changes in heart rate were, however, recorded in the horse administered with the lowest dosage (3.5 mg/kg).
• It was also noted that glucose concentrations significantly changed in all dose groups studied.

Conclusion of the Study

• The study concludes that similar to results in human tests, meldonium exhibits a prolonged detection time in biological samples collected from horses.
• This finding indicates that effective regulation and detection of meldonium usage in performance horses can be achieved.
• It also infers a need for authorities to be more watchful of potential abuse of meldonium in equine sports due to its prolonged detection time and significant impact on glucose concentrations.