Amitraz, Preventic, pyrethrins, pyrethroids, organophosphates, carbamates
Toxicity to pets
Flea and tick collars vary in their active ingredient. Often, these collars contain amitraz (a chemical that is an alpha2-adrenergic agonist and monoamine oxidase inhibitor), organophosphates or carbamates, or pyrethrins/pyrethroids. Please see each individual active ingredient for more information. When flea and tick collars are accidentally ingested or applied to pets inappropriately, they can result in severe clinical signs of the central nervous system (e.g., lethargy, walking drunk, dilated pupils, seizures, coma), gastrointestinal system (e.g., drooling, vomiting, diarrhea, bloating), and cardiac system (e.g., slowed heart rate, low or high blood pressure). Depending on what the active ingredient is, treatment must be initiated promptly. Removal of the flea collar is also important!
The content of this page is not veterinary advice. A number of factors (amount of substance ingested, size of the animal, allergies, etc.) determine what is toxic to a particular pet. If you think your pet has eaten something potentially toxic, call Pet Poison Helpline or seek immediate veterinary treatment.