The Ivermectin Overdose Dilemma

Take your pet parenting knowledge to the next level by knowing about ‘Ivermectin Overdose’ and how you can safeguard your furry friends from it.
–by Dr Anuradha Nema and Dr Vichar Nema


Ivermectin, an anti-parasitic drug widely used to treat endo and ectoparasites in humans, various animals, including dogs. The drug is otherwise safe at the recommended doses for dogs, but it can be toxic if given in excess amounts.

Certain dog breeds like – Collies, Shetland Sheepdogs, Australian Shepherds, and related herding breeds, due to some genetic mutations are unable to metabolize the drug properly and are more sensitive to ivermectin toxicity at even low doses. Ivermectin can build up in the central nervous system, leading to neurological symptoms and potentially life-threatening complications. However, it’s important to consider that not all dogs will experience toxicity, and the severity of symptoms may vary as per the individual sensitivity, dose ingested, and duration of exposure.

Symptom Spotlight

Symptoms of ivermectin toxicity can include –

  • Neurological symptoms: Staggering with uncoordinated movements, tremors, disorientation, dilated pupils, seizures, and coma or death (in severe cases).
  • Blindness or impaired vision: Ivermectin toxicity can potentially lead to vision problems and blindness in dogs, especially susceptible breeds. Drug has severe impact on central nervous system, optic nerve and retina of eye. This leads to degenerative changes in parts of the eye responsible for processing visual information. Pet may suffer from vision impairment or complete loss of vision. While the blindness caused by ivermectin toxicity can be permanent, prompt medical intervention may help minimize further damage and provide supportive care to improve the dog’s overall well-being.
  • Gastrointestinal issues: Vomiting, diarrhea, and loss of appetite.
  • Other symptoms: Dogs may exhibit depression, lethargy or weakness, excessive drooling, weakness, and respiratory distress.

If you notice any of these symptoms, take your pet to the vet immediately for early detection and right course of treatment. Prompt consideration and intervention is crucial for your pet’s health and wellbeing.It can help mitigate the severity of toxicity and potentially prevent long-term complications, including blindness.

Decoding diagnosis and triumphs of treatment

The veterinarian will perform a thorough examination, assess the symptoms, and may run diagnostic tests to confirm and evaluate the extent of toxicity and any ocular damage with its impact on your pet’s vision.

Treatment for ivermectin toxicity often involves supportive care to manage the symptoms. This may include intravenous fluids, anti-seizure medications, medications to control vomiting, activated charcoal administration to prevent further absorption of the toxin, and other supportive measures. The veterinarian may also induce vomiting or perform gastric lavage to remove any remaining ivermectin from your pet’s stomach.

Always provide medications to your furry friend with proper veterinary guidance.

(Dr. Anuradha Nema – Assistant Professor, CVSc& AH, Rewa, Madhya Pradesh, Dr. Vichar Nema, Second In-Command – DTBC, SSB, Dera, Rajasthan)