Our old beagle had this, and we tried EVERYTHING to get rid of it. Expensive meds from the vet, changing foods, different shampoos, creams and powders. Finally one of our friends who raises beagles and fought this problem suggested "Horseman's Dream Fung-a-way tropical fungicide" It's made for horses dogs and cats. We bought ours pretty cheap at TSC and it has been a DREAM. Takes about three days for them to totally stop, and our beagle needs it about once a week, but she's stopped rubbing her back all over everything. Good luck!