Petco Text Logo
Petco Pet Logo

  • Two Easy Ways to Start Earning Rewards!

My cat accidentally ate dog's Thyrosyn. Should I be worried?

Updated On September 23rd, 2025

Pet's info: Cat | Siamese | Female | spayed | 10 years and 4 months old | 8 lbs

I posted earlier but it went away. I accidently gave my half of my dog thyrosyn 5 mg to my cat before I shaved her. I thought it was her new sedative. She acts fine and it been 3 hrs since I gave it to her. Should I be worried. I like to go to sleep tonight knowing everything will be alright.

2 Answers

Most Helpful Answer

Image profile

Answered By Destini R. Holloway, DVM

Veterinarian

Published on August 15th, 2018

Most Levothyroxine tablets come in 0.1-0.9mg dosages, so I am not sure why your pet is on a full 5mg dosage. If this is not a typo, then this is a pretty hefty dosage for a cat to receive if she surely got 2.5mg's. However, severe life threatening symptoms from a single overdose are less likely than with chronic overdosing. Some signs you may see are: Vomiting, diarrhea, hyperactivity to lethargy, hypertension, tachycardia, tachypnea, dyspnea, and abnormal pupillary light reflexes. It can take 1-9 hrs for absorption to occur. Then the drug should be mostly out of her system 12-24 hrs. In most cases this is not an emergency situation, but you can see the symptoms I mentioned above, which should be treated with supportive care through your vet. This is a tough one indeed, but it is likely that Kilala will be ok, since I assume that the dosage you gave has to be incorrect based on the typical dosage that dogs receive (between 0.1-0.9mg). I hope that everything works out well for your pet Kilala. Best wishes and take care!

Vote icon

1Pet Parents found this answer helpful

Other Answers

  • Image profile

    Answered By Rodrigo Roca, DVM

    Veterinarian

    Published on

    Hello, sorry to hear about Kilala. She may develop abnormal heart rates/rhythm and blood pressure changes which could cause her to need medications to control this. However, given that it has been 3 hours since she ingested it may be too late to induce vomiting. The next best step is to call the ASPCA poison control line to inquire about the toxicity risk with this dose of medication. ‭(888) 426-4435‬ You should plan to have her evaluated by your veterinarian or emergency clinic tonight, especially if ASPCA recommends it. Mild signs of this increased drinking, urination, excitability, panting, and a ravenous appetite. Hope this helps and best of luck

    Vote icon

    1Pet Parents found this answer helpful

See More Answers

Related Questions

Petco Pet Education Center
Health & Wellbeing
What to do if my cat has a small hole with pus coming from its ear?
Is your cat's ear hole oozing pus? A Petco vet explains potential infections like abscesses from bites, advising immediate vet care, antibiotics, and recovery.
Updated on September 23, 2025
Petco Pet Education Center
Health & Wellbeing
My male dog's penis is stuck out and his scrotum has a painful rash.
Is your 11-year-old male dog experiencing a painful penis or rash? A certified vet explains potential paraphimosis urgency and why immediate care is vital.
Updated on September 23, 2025
Petco Pet Education Center
Health & Wellbeing
What fish dog food helps dry skin if my dog eats Science Diet?
Is your dog's dry skin a concern? A certified vet offers expert advice on finding the best fish-based dog food alternatives to Science Diet for essential oils.
Updated on February 04, 2026
Petco Pet Education Center
Health & Wellbeing
Dog licking paws, fur loss, and jaw wound: Could it be allergies?
Is your Shih-Tzu crossbreed biting his feet, losing fur, or has a wound? A trusted vet explains these classic allergy signs and advises on treatments like Apoquel or medicated shampoo.
Updated on September 23, 2025
Petco Pet Education Center
Food & Nutrition
Is there a chart for dog food protein biological value and digestibility?
Dog food protein's biological value & digestibility: A vet explains why data is complex. Learn to judge quality by company reputation and your dog's health.
Updated on September 23, 2025
Petco Pet Education Center
Health & Wellbeing
Why does my puppy have bloody, mucousy stools despite diet changes?
Your 4-month-old puppy suffers from ongoing loose stools with mucus and blood. An expert veterinarian explores potential intestinal parasites and advises further fecal testing. Find answers here!
Updated on September 23, 2025
image
Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Book Now

Sponsored