Somehow Moose managed to get fleas. The vet recommended Capstar. Within 30 minutes the fleas started running to the surface of his fur and abandoning ship. During this time Moose was going crazy and trying to groom himself as the fleas ran across his body. After about 25 minutes of that he passed out and has been more relaxed than he has been all weekend. Capstar is a solid product and I would highly recommend it.