Will Falconer, DVM Moderator
I'm with you, JoKarol. That's a load of toxic stuff! I've got a popular page called Non-toxic Flea (and Tick) Control and another on Drug Free Heartworm Prevention you may want to visit.
You'll also want to visit my Resources page for the AVH list there, and get a veterinary homeopath hired to get your pup back to healthy.
All the best to you.