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Ivermectin toxicosis in dogs: a retrospective study
Valentina Merola1, Safdar Khan, Sharon Gwaltney-Brant
1ASPCA Animal Poison Control Center, 1717 South Philo Road, Suite 36, Urbana, Illinois 61802, USA.
Summary
Ivermectin overdose in dogs can cause serious issues, even at lower doses than previously thought. Some dogs, particularly those with p-glycoprotein defects, are more susceptible to ivermectin toxicity.
Area of Science:
- Veterinary Pharmacology
- Toxicology
- Canine Medicine
Background:
- Ivermectin is a widely used antiparasitic drug in veterinary medicine.
- Overdoses of ivermectin can lead to severe adverse effects in dogs.
- Genetic factors, such as p-glycoprotein defects, may influence ivermectin sensitivity.
Purpose of the Study:
- To evaluate canine exposures to ivermectin.
- To determine the relationship between ivermectin dosage and clinical signs.
- To assess the role of p-glycoprotein defects in ivermectin toxicosis.
Main Methods:
- Retrospective study design.
- Analysis of canine exposure cases from 1998 to 2005.
- Evaluation of ivermectin dosage, clinical signs, animal signalment, and p-glycoprotein status.
Main Results:
- Clinical signs of ivermectin toxicity were observed at lower doses than previously reported.
- Some dogs exhibited increased susceptibility due to p-glycoprotein defects or other factors.
- Adverse effects can occur even at doses considered low-risk for certain breeds.
Conclusions:
- Veterinarians should be aware of potential ivermectin toxicity at lower dosages.
- Individual factors, including genetic predispositions like p-glycoprotein defects, increase susceptibility.
- Careful dosage monitoring is crucial to prevent ivermectin toxicosis in dogs.
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