Dog is licking skin raw

Question
Hello my name is Linda. Thank you for taking the time to answer my question. My 5 year old rat terrier Fritz is licking the hair off his tail and making the skin raw. We treated him for fleas two weeks ago with front line and this problem didn't start until 4 or 5 days ago. We thought maybe it was fleas but didn't want to treat him with any flea products since we just put frontline on him 2 weeks ago. He has had flea issues in the past and has had skin staff infection twice on his stomach. Do you think it could be fleas again after treating him with frontline? Can we treat him again with a flea product so soon after the frontline treatment? It doesn't look like staff infection this time but I worry about it since he's had it before. Thank you so much again for taking the time to help people and their pets.
Linda

Answer
More than likely he is suffering from flea allergy. You can kill all the fleas on him and he will still have an itchy skin reaction for several weeks after the last flea bite.  You should have your vet give him some steroids to calm down his skin while you are working on the flea problem.