Concurrent ivermectin and Solanum spp. toxicosis in a herd of horses.

The research paper reveals that horses, which ingested a species of toxic plants in the Solanum family concurrently with being administered ivermectin, displayed signs of ivermectin toxicity, despite the drug dosage being appropriate. This was observed in a herd of horses that demonstrated sudden onset of neurological symptoms. Recovery was achieved in all cases through supportive care.

Objective and Method

• The study aimed to present and analyse the clinical symptoms of horses intoxicated by ingesting Solanum species while being administered ivermectin.
• Six out of eleven affected horses were taken in for evaluation and treatment. The remaining five affected horses were treated on the farm while the four horses kept separately showed no signs of intoxication.
• This study accounts for the cases in form of a series.

Investigation and Findings

• Investigation was performed by analysing serum ivermectin concentrations in the six hospitalized horses.
• The remaining paste of ivermectin from the tubes was also analyzed for its concentration.
• The hay consumed by the affected horses was scrutinized for the presence of toxic plants.
• Interestingly, the serum concentrations of ivermectin in affected horses were found to be higher than what would be expected given the dosage of the drug that was administered. The unused ivermectin left in the tubes was found to be within its specified concentration limits.
• Furthermore, the hay consumed by the horses was found to be heavily contaminated with two species of the Solanum plants.

Conclusion

• Despite the standard dosing of ivermectin, signs of ivermectin toxicity were apparent, this occurrence was linked to the concurrent consumption of Solanum family toxic plants.
• All the horses were eventually able to return to their normal neurological function after receiving supportive care.