My cat ate moxidectin – what should I do?

Updated 2026-09-30 · 1 sources

Based on: Pet Poison Helpline

Call a vet now

Call your vet or the nearest emergency vet right now. Moxidectin is toxic to cats and can cause drooling, tremors, seizures, coma, dilated pupils, or death.

What to do now

What to do right now

  1. Call your vet or the nearest emergency vet.
  2. Note what was eaten, how much, and when.
  3. Bring the packaging.
  4. Keep your cat calm.
  5. Remove what is left.

Don't

  • Do not make your cat vomit unless a vet tells you to.
  • Do not give any human medicine.

Why it can be dangerous

Moxidectin is an anthelmintic, a drug that kills parasites.[1] Moxidectin is commonly used as an active ingredient in monthly heartworm preventatives.[1]

Signs to watch for

  • Drooling
  • Tremors
  • Seizures
  • Coma
  • Dilated pupils
  • Death

Where it is found

  • Monthly heartworm preventatives
  • Equine dewormer
If your pet is struggling to breathe, has collapsed, is having a seizure or can't stand up: go to the nearest vet now.

Not sure how serious it is?

OkPaw asks a few quick questions about your pet and tells you in 30 seconds whether it can wait. Free on Google Play for Android.

Get it on Google Play

OkPaw is on Android now – an iPhone version is on its way.

Common questions

How much moxidectin is dangerous?

Call your vet or the nearest emergency vet right now.

Which signs should I watch for?

Call your vet or the nearest emergency vet right now.

What should I do now?

Call your vet or the nearest emergency vet right now.

Sources

  1. Pet Poison Helpline

How this page was made: written with the help of AI from the sources below, then checked claim by claim against those sources. Urgency levels follow OkPaw’s fixed safety rules. It is guidance, not a diagnosis. How we write our pages

The same page for dogs →

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