In cases that involve pneumonia or other advanced respiratory disease, the attending veterinarian may recommend empirical antibiotic treatment while waiting for the results of culture and sensitivity on samples of upper respiratory tract secretions. The results of those tests will identify which pathogens are causing the dog’s illness, and will enable the veterinarian to select the best antibiotic or antiviral therapy. Empirical antibiotic therapy is a “let’s-take-our-best-guess” approach that often is successful and has few, if any, adverse side effects (except for possible gastrointestinal upset and contribution to antibiotic resistant strains of infectious bacteria). Dogs with bacterial pneumonia usually are treated with antibiotics for 1 to 4 weeks after the radiographic signs of pneumonia are resolved. A veterinarian is the best person to recommend an appropriate treatment protocol for a dog showing signs of upper respiratory tract disease.