interceptor should only be given once a month. My dogs take it .It is for heartworms but also controls hookworm,roundworm and whipworm. One of the reasons I chose interceptor is because it controls whipworms. Mandy had them once and they say they can live in your soil for years.If your dog is pooping out the worms that should be a good sign.Maybe you could call your vet if you have any questions to be sure.