The active ingredient in Comfortis^® is spinosad. When ingested by fleas, spinosad targets the flea’s nervous system, causing the flea to show involuntary muscle contraction and tremors. Spinosad-induced excitation leads to flea paralysis and rapid death.

While extremely toxic to fleas, Comfortis is safe for dogs at the label dose. Dogs do not have the same response to Comfortis.

Because you give Comfortis to your pet orally, you do not have to tolerate the mess and inconvenience of topical pesticides. Comfortis is rapidly absorbed in your dog’s bloodstream, where it circulates and protects your dog from flea infestation for a full month. Comfortis begins killing fleas within 30 minutes, so you know your dog is getting fast relief and long-lasting protection.

Comfortis does not depend on your dog’s skin and hair coat to distribute across the body. That’s why Comfortis is a great choice for dogs with skin problems, as flea protection is vitally important and cannot be compromised.

The introduction of spinosad for use in agriculture resulted in the receipt of a Presidential Green Chemistry Challenge Award* in 1999 from the U.S. Environmental Protection Agency. The award was presented to Dow Agro Sciences LLC in the category of "Designing Safer Chemicals" for the introduction of spinosad as an insect control product for use on crops. This award demonstrates that spinosad as a technology for insect control has a favorable environmental profile. This award is not relevant to the safety and efficacy of Comfortis, nor does it confer any environmental benefit to Comfortis.

Important Safety Information

• The most common adverse reaction reported is vomiting.
• Other adverse reactions reported in decreasing order of frequency are: depression/lethargy, decreased appetite, incoordination, diarrhea, itching, trembling, excessive salivation and seizures.
• Following concomitant extra label use of ivermectin with Comfortis^®, some dogs have experienced the following clinical signs: trembling/twitching, salivation /drooling, seizures, incoordination, excessive dilation of pupils, blindness and disorientation.
• Post approval experience continues to support the safety of Comfortis when used concurrently with heartworm preventatives according to label directions.
• Click here for full product label including complete safety information.