Pharmacokinetics and safety of silibinin in horses.

The research article discusses the study conducted to identify the bioavailability, pharmacokinetics (how the body processes a drug), and safety of silibinin, a milk thistle derivative, in healthy horses.

Methodology and Process

• The researchers started the study by administering silibinin through intravenous (IV) and by orally feeding and nasogastric tube (a tube passed through the nose and throat into the stomach).
• During the experiment, five out of nine horses received increasing doses of silibinin over four nonconsecutive weeks. This regime involved starting with no dosage and then gradually switching to twice daily doses of 6.5 mg/kg, 13 mg/kg, and finally 26 mg/kg of body weight for seven days each week.

Results and Findings

• The researchers found that the bioavailability, which is the degree and rate at which a substance is absorbed into the living system, of orally administered silibinin phospholipid (the form in which the substance silibinin was given), was quite low – 0.6% when given in feed and 2.9% when administered via a nasogastric tube.
• It was observed that the drug’s pharmacokinetics was nonlinear, meaning the process by which the drug moves in, through, and out of the body was not in a straight line or pattern.
• The study also found that despite being administered twice daily, silibinin did not build up in the horse’s body when given at the evaluated doses.
• Importantly, no toxicosis or poisoning due to excessive drug intake was observed even at the highest dosage level.

Conclusion

• The study concludes that silibinin phospholipid is safe for horses, despite it having low bioavailability.
• Lastly, the researchers suggest further study in horses suffering from hepatic or liver diseases given the implications for potential use in treating these conditions.