I just adopted a 2 year old standard poodle. He's 70 pounds but gentle. He came w/an ear infection that wasn't too serious. I've followed the cleaning and antibiotic instructions to a "t". He just started to scratch his ears again. Is it likely that the infection is still present after 2 weeks of antibiotics? I wash the ears every day. They don't appear to be secreting the brownish stuff like when I adopted him. What is the best way to keep the ears from having chronic infections?