The purpose of this study is to decrease unnecessary antibiotics prescribed to hospitalized patients for possible pneumonia by flagging patients with respiratory rates and oxygenation levels within reference ranges given prior data suggesting that discontinuing antibiotics in this population is safe. Patients will be randomized to 3 arms: 1) usual care, 2) electronic alert, or 3) pharmacist outreach.

Prior data suggest antibiotic starts for patients with normal vital signs are common and there does not appear to be harm associated with stopping antibiotics after only 1 or 2 days in patients with normal oxygen saturations. We therefore propose a pilot patient-level three-way randomized trial to determine the best way to operationalize professional society recommendations for post-prescription antibiotic reviews amongst patients started on antibiotics with a stated indication of pneumonia despite normal respiratory rates and oxygenation levels. If the patient's median respiratory rate and oxygen saturation is normal after 1-2 days of antibiotics they will be randomized to usual care versus a EHR-based best practice alert versus pharmacist outreach. The EHR-based best practice alert will highlight the patient's normal respiratory rate and oxygenation and encourage stopping antibiotics if there isn't another indication for antibiotics. Pharmacist outreach will involve contacting the responding clinician or attending physician to determine the working diagnosis, review the patient's vital signs, and to ask the team to consider stopping antibiotics if there are no clear indications for antibiotics. In all cases, the final decision on whether to stop or continue antibiotics will be up to the primary team. We will assess the impact of these post-prescription review strategies to decrease unnecessary antibiotic utilization on antibiotic utilization (antibiotic days and antibiotic-free days) compared to usual care. Safety outcomes will include time to discharge, readmissions, hospital-free days, and mortality. We will also assess for change in the primary outcome over time.

Inclusion Criteria:

• All patients admitted to Brigham and Women's and BWH Faulkner Hospitals and prescribed antibiotics with a stated indication of pneumonia who have a median respiratory rate of ≤20 and oxygen saturation of ≥95% without supplemental oxygen sustained for at least 24 hours.

Exclusion Criteria:

• Patients under 18 years old, patients on transplant and oncology services, patients who are pregnant, patients in an intensive care unit, patients with cystic fibrosis or bronchiectasis, patients on immunosuppressive medications, and patients with positive blood cultures (other than common skin contaminants)