Class of 2012 Abstract / Specific Aims: Cellulitis accounts for the majority of skin and skin structure infections in patients who present to the emergency departments in the United States. The primary objective of this study was to evaluate the appropriateness of empiric cellulitis therapy prescribed in an emergency department of an academic medical center. The secondary objective of the study was to compare the cost-effectiveness of the empirical cellulitis therapy prescribed at the institution. Methods: This retrospective chart review study has been approved by the Institutional Review Board. Adult patients evaluated at an emergency department of a tertiary care, academic medical center, diagnosed with cellulitis and prescribed empiric antibiotic therapy between October and November 2010 were evaluated. Subjects were excluded if they required hospitalization or surgical intervention in an operating room or if they were diagnosed with necrotizing fasciitis, orbital cellulitis, or a diabetic foot infection. Data collected for each subject included type of cellulitis, therapy prescribed, and outcomes. Appropriateness of empiric cellulitis therapy was determined by expert opinion and guideline statements. A chi- square test was used to evaluate the statistical significance of treatment failure between the prescribed antibiotic groups. An independent t-test was used to analyze the cost between the prescribed antibiotic groups. An incremental cost-effectiveness ratio was used to determine the cost- effectiveness of the prescribed antibiotic groups. Main Results: The majority of patients were given a prescription for either clindamycin montherapy (37%) or trimethoprim-sulfamethoxazole plus cephalexin (40%) as empiric therapy when discharged from the emergency department. While follow-up (either repeat emergency department visit or clinic visit within the academic medical healthcare network) was only available in 78% of subjects, there was no statistical difference (p=0.51) in therapy outcomes between these two empiric therapy groups. Conclusions: Types of antimicrobials, doses, and duration of therapy prescribed for outpatient empiric cellulitis therapy at a single medical center were not consistent.