Pharmacokinetics of intravenously and orally administered sotalol hydrochloride in horses and effects on surface electrocardiogram and left ventricular systolic function.

This research paper looks at the study of how Sotalol Hydrochloride, a drug for treating irregular heartbeats in humans and small animals, works when introduced to horses. The study aims to understand how the drug is absorbed and distributed in the body of the horse and how it affects the horse’s heart rhythm and the performance of the left ventricle.

Study Methodology

• Six healthy horses were used for this study. Each was administered Sotalol Hydrochloride (STL) either intravenously (IV) or orally (PO) at a dose of 1 mg per kg of the horse’s body weight.
• A series of blood samples were taken before and at various intervals after the administration of STL to measure plasma STL concentrations.
• In order to monitor the heart’s reaction to STL, Electrocardiography and Echocardiography examinations were performed at different time intervals before and after IV administration of STL.

Research Findings

• The study found that after being administered intravenously, the peak plasma concentration was significantly higher at 1624 ng/mL as opposed to oral administration which resulted in a mean peak plasma concentration of 317 ng/mL.
• The oral bioavailability of STL was found to be intermediate (48%), with maximal absorption occurring after 0.94 hours.
• STL had a moderate distribution throughout the horses’ bodies and it took roughly 15.24 hours for half of the drug to be eliminated from the body.
• The research found that IV administration resulted in a significant increase in QT interval – a component of the heart rhythm – but other parameters of the horse’s heart were not significantly changed.
• In terms of side effects, Transient transpiration (temporary sweating) was observed after IV administration, but no adverse effects were noticed after a single oral dose of 1 mg/kg STL in any of the horses.

Conclusions

The research concluded that Sotalol Hydrochloride has an intermediate oral bioavailability in horses, and it is potentially useful in treatments aiming to correct abnormal heart rhythms. This leads to an indication that STL could potentially be used for treating equine arrhythmias.