The EPA has been working with the company for some time to address the 7,100 complaints they have received from 1998 to 2003 about the drug causing illness in pets. The chemical that is likely causing the problem is pyrethrin. It is used in most over-the-counter flea and tick products. Louisiana SPCA veterinarians say it can cause problems in dogs and is only effective for about a week. The chemical can be harmful to cats. Your veterinarian will likely prescribe a flea and tick product that contains fipronil or imidadoprid, which are considered much more effective. “We don’t encourage giving anything over the counter to your pets without asking your veterinarian about it first,” advises one of our veterinarians. Please remember that pet store employees are not veterinarians, and they aren’t trained to give you medical advice. Source: Laura Maloney tp article