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Why is my dog twitching and restless after recent flea treatment?

Updated On September 23rd, 2025

Pet's info: Dog | Shih Tzu | Male | neutered | 9 years and 11 months old | 20 lbs

our dog has recently started twitching constantly and wants constant attention . Had a new haircut and nails cut about 4 days ago and has received his flea/ tick prevention 3 days ago .

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4 Answers

Most Helpful Answer

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Answered By Destini R. Holloway, DVM

Veterinarian

Published on April 21st, 2019

Poor guy. It sounds like he may be having muscle spasms from the flea prevention, since this is a common side effect seen. I would recommend washing him again to remove the product and then visiting your vet to have him treated for his muscle spasms. A muscle relaxer likely will be recommended as well as any other supportive care meds he needs. I would also make a note to avoid using the flea preventative in the future if this is deemed to be the cause. I hope that your pet Max feels better soon! Best wishes and take care.

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    Answered By Ann Dion, DVM

    Veterinarian

    Published on January 11th, 2019

    Hello and welcome to Petco Pet Education Center, formerly Petcoach. Toxicity from flea products usually lead to tremors/seizures that don't stop right away, they often continue. If your cat had a quick seizure (lasting about 1 min and then stopping completely), then this was likely unrelated to the seizure medication. Also, if the seizure stopped, then unless you re-apply the medication, it should not occur again. It is possible that your cat is having seizures for different reasons then the medication. If your cat was tremoring for a bit of time that slowly resolved (over many hours or even days), and is now stopped, and hasn't occurred again, this could be from the medication, and no intervention is required, just don't use that medication again. Best of luck with your little one!

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    Answered By Dr. Elizabeth

    Veterinarian

    Published on June 4th, 2019

    I recommend to have Butters examined quickly by the veterinarian. Bring in the flea medication and the deworming medication. It is possible he is having a reaction to the medication which needs to be addressed quickly. Also scan the house for any medication, drugs or other toxins that Butters could have gotten into. There are also possible metabolic and infectious causes as well but you can't know without an exam and likely bloodwork. Best of luck and I hope he recovers quickly.

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    Answered By Dr. Leigh, DVM

    Veterinarian

    Published on May 1st, 2017

    I am not sure the type of flea medication that you used but it sounds like he is having a reaction to the medication. Some flea medications can be toxic to cats so he needs to be seen by a vet ASAP. If your vet is not open than you should take him to an emergency clinic for treatment.

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