Chows often have allergic reactions to flea treatments. Trifexis is new on the market and has had many reports of causing serious health issues. We recently found out two Chow Chows died within hours of being given this medication. If you do some research online you will find many complaints where dogs have become ill and had to be taken to the emergency care.
Chows can be very sensitive to topical or oral treatments. Be extremely careful of this medication!