My greyhound had tapeworms twice. Both times he didn't have fleas, but was around a dog that did. Probably ate one flea and that was it. When I got Cooper, he had tapeworms, too. But no fleas, no room on his skin for them! I'm sure he was probably surrounded by them at his old house, though. One pill typically clears them up. Cooper actually had 2 pills spaced 2 weeks apart, but the first one actually knocked them out.