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Suspected ivermectin toxicosis in a miniature mule foal causing blindness
Caryn E Plummer1, Maria E Kallberg, Franck J Ollivier
1Department of Small and Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610-0126, USA.
Veterinary Ophthalmology
|January 18, 2006
Summary
An overdose of ivermectin dewormer caused acute blindness and ataxia in a young mule foal. Prompt supportive care led to a full recovery, indicating a reversible central nervous system effect.
Area of Science:
- Veterinary Neurology
- Toxicology
- Ophthalmology
Background:
- Ivermectin is a widely used antiparasitic drug in veterinary medicine.
- Overdoses can lead to adverse effects, but specific neurological impacts in equids require further understanding.
Observation:
- A 9-week-old miniature mule foal presented with sudden blindness, ataxia, and depression.
- The clinical signs appeared after accidental overdose of an ivermectin-based dewormer.
Findings:
- Ophthalmic and electrodiagnostic evaluations ruled out primary retinal disease.
- Findings suggested a central neurologic effect of ivermectin toxicity was responsible for the blindness.
Implications:
- This case highlights the potential for central nervous system toxicity from ivermectin overdose in foals.
- Symptomatic and supportive treatment can be effective in managing ivermectin-induced neurological deficits.
- Further research into the neurotoxic mechanisms of ivermectin in equids is warranted.
