Pharmacokinetic disposition of dimethyl sulfoxide administered intravenously to horses.

The research observed the behavior of the drug dimethyl sulfoxide (DMSO) when administered intravenously to horses, noting how the different doses affected how the drug was used up and disposed of by horses’ bodies over time.

Experiments Conducted

• Researchers administered DMSO intravenously to six Thoroughbred horses.
• Two different doses, namely 1.0 g/kg and 0.1 g/kg were used.

Observations and Findings

• The pharmacokinetics of the drug appeared to be linear, meaning that changes in dosage led to proportional changes in the body’s response.
• The biological half-lives of the drug for the two dosages were 8.6 +/- 0.3 hours and 9.8 +/- 2.2 hours, respectively. The half-life of a drug is the time it takes for the body to reduce the concentration of the drug to half its initial dose.
• At 12 hours after a 1.0 g/kg dose was administered, 26.6% of the DMSO dose was excreted unchanged into the urine; at the same time frame after a 0.1 g/kg dose was administered, 25.3% of the DMSO dose was excreted unchanged into the urine.
• Predictions were made that 29.4% and 40.6% of the total DMSO dose would be excreted into the urine for the 1.0 g/kg and 0.1 g/kg dosages, respectively.
• The researchers found that a 10% DMSO concentration in normal saline solution was safe to administer as a rapid IV infusion.

Recommendations

• For more concentrated solutions, slow administration is recommended. This is to avoid any potential rapid reactions or overload in the body with the drug.
• Based on the half-life observed, researchers suggested that DMSO should be administered two times a day intravenously for the treatment of increased intracranial pressure and/or cerebral edema in horses. This recommendation is targeted specifically for Vets and horse caregivers to help manage these conditions.