I treated my cat with advantage on oct 22, but he still has fleas. At first they seemed to go away, but now he's scratching again and i actually saw one today. Is it dangerous to put more advantage on him so soon and if so is there anything that I can do? He's indoor/outdoor due to my living situation so I can't really keep him away from fleas right now, I figured advantage would work even for cats that go outside. Any ideas?