Comfortis (Rx)

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Comfortis (Rx)
Comfortis® is the first FDA-approved, chewable, beef-flavored tablet that kills fleas and prevents flea infestations on dogs and cats for a full month. Each tablet contains spinosad.
 
 
 
 

Safety Information

  • Comfortis starts killing fleas within 30 minutes and provides a full month of protection.
  • It is approved for dogs 14 weeks and older and cats 14 weeks and older, weighing the appropriate minimum pounds for their formulation.
  • Most side effects are mild but can include vomiting, diarrhea, lethargy, and loss of appetite.
  • If vomiting occurs within an hour of dosing, consult your vet; another full dose may be needed.
  • Comfortis should not be used in pets with a known allergy to spinosad.

Warnings 

  • Not for use in puppies or kittens younger than 14 weeks.
  • Use caution in pets with pre-existing seizure disorders, as rare neurologic effects have been reported.
  • Avoid accidental ingestion by humans—keep out of reach of children and other animals.
  • Contact a veterinarian immediately if you suspect an overdose or adverse reaction.

Human Warnings

  • For animal use only.
  • Wash hands after handling tablets.
  • In case of accidental ingestion, seek medical help immediately.
  • Do not handle the product if you are allergic to its active ingredient, spinosad.


References

  1. Elanco. Comfortis® (Spinosad) for Dogs and Cats. Elanco, 2025, https://my.elanco.com/us/comfortis.

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