I gave my dog Comfortis for fleas last night, and she seems a bit lethargic now—is this normal?

I gave my dog Comfortis for fleas last night, and today she seems a bit more lethargic than usual. She’s normally pretty active in the morning, but today she’s been lounging around quite a bit. Is this a normal reaction after taking flea medication, or something I should be concerned about?

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Answer

It's understandable to be concerned when your dog displays unusual behavior after taking a new medication. Lethargy can be a side effect of Comfortis, but it’s generally mild and temporary.

  • Monitor your dog's behavior over the next 24 hours.
  • Provide plenty of fresh water and a comfortable resting area.
  • Contact your veterinarian if symptoms persist or worsen.

Comfortis is a popular oral flea medication for dogs and generally well-tolerated. Some pets may experience mild and temporary lethargy as a side effect, which typically resolves on its own. Keeping an eye on your dog and ensuring she stays hydrated can help, but if the lethargy continues or other concerning symptoms arise, consulting your vet is a good idea.

Book a consultation with a licensed vet at Dial A Vet for just $49 AUD if you're unsure or symptoms are getting worse.

Frequently Asked Questions

  • Is lethargy a common side effect of Comfortis?

    Yes, lethargy can occur, but it is usually mild and temporary. If your dog remains lethargic or develops other symptoms, contact your vet.

  • What should I do if my dog's symptoms worsen?

    If symptoms like severe lethargy, vomiting, or other unusual behaviors develop, it's best to consult your veterinarian promptly.

  • Can I give my dog anything to help with the side effects?

    Ensure your dog has access to water and a comfortable place to rest. Avoid administering additional medications without veterinary advice.

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Disclaimer: The customer and expert messages presented herein may have been altered with artificial intelligence or modified to enhance readability and safeguard the privacy of individuals. This content is for informational purposes only and is not a substitute for professional veterinary advice, diagnosis, or treatment. If your pet is experiencing a medical emergency, contact your local veterinarian or emergency animal hospital immediately. Talk to a vet now.

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