OBJECTIVES: Antibiotic resistance in the United States adds $20 billion in excess direct health care costs and judicious use of antibiotics slows the emergence of resistant bacteria. Up to 50% of all the antibiotics prescribed are not needed or are not prescribed appropriately. Appalachia has high rates of antibiotic prescribing, ranging from 0.773 to 1.274 per person annually. This study sought to identify characteristics of prescribers and patients associated with a higher number of antibiotic prescriptions. METHODS: The research design is a cross-sectional, observational study.  Beneficiaries of a public insurance program in fiscal year 2015, with a claim in prescription and medical claims files were included. The prescriber characteristics were extracted from the National Provider Enumeration System.  The outcome was the number of antibiotic prescriptions per prescriber during the study period.  Negative binomial regression was used to analyze the association between prescriber characteristics and the number of antibiotic prescriptions. RESULTS: The cohort contained 138,937 patients and 23,982 prescribers. The patients were predominantly female (57%) with a mean age of 41.2 years (SD=19.4) while the prescribers were mostly male (58.5%) with allopathic or osteopathic credentials (65.6%). There were 7.6 (SD=27.8) antibiotic prescriptions written per prescriber and 1.32 per patient in the 12 months. Prescribers who treated more patients in general (Incidence Rate Ratio=1.04 CI 1.03,1.04), who had a diagnosis with an indication for antibiotics (IRR=1.78 CI 1.63,1.95), and who were dentists (IRR=4.76 CI 4.38,5.17) prescribed more antibiotics. Prescribers who treated a higher percentage of women (IRR=0.70 CI 0.65,0.76) and patients over 50 years (IRR=0.54 CI 0.50,0.59) prescribed fewer. Prescriber gender was not associated with the number of antibiotic prescriptions. CONCLUSIONS: A higher than average number of antibiotic drugs were prescribed to patients in the cohort over 12 months. This study identified prescriber characteristics that could be targeted with experimental studies to reduce antibiotic prescriptions.