Compare to K9 Advantix: Activate II uses Imidacloprid, Permethrin, and Pyriproxyfen - the same safe, fast acting and effective active ingredients used in Advantix II for Dogs. Activate II for Dogs starts to kill fleas and ticks within 24 hours, and continues actively protecting your dog for up to 30 days with each application Vet approved for medium dogs 11 to 20 pounds: Activate II topical flea drops were developed by veterinarians to repel and kill fleas and ticks on contact, no flea bites required. Oral flea meds, pills, and chews only work after your pet is bitten by a pest, exposing your dog to potential flea borne illnesses Break the Flea Lifecycle: Activate II stops and controls infestations by breaking the flea life cycle. Our flea treatment use an insect growth regulator (IGR) to prevent re-infestation by killing flea eggs and larvae so your dog can KICK the ITCH