Background: Rates of sepsis/septicemia hospitalization in the US have risen significantly during recent years, and antibiotic resistance and use may contribute to those rates through various mechanisms.Methods: We used multivariable linear regression to relate state-specific rates of outpatient prescribing overall for fluoroquinolones, penicillins, macrolides, and cephalosporins between 2011-2012 to state-specific rates of hospitalization with septicemia (ICD-9 codes 038.xx present anywhere on discharge diagnosis) in each of the following age groups of adults: (18-49y, 50-64y, 65-74y, 75-84y, 85+y) reported to the Healthcare Cost and Utilization Project (HCUP) between 2011-2012, adjusting for additional covariates, and random effects associated with the ten US Health and Human Services (HHS) regions.Results: Rates of penicillin prescribing were positively associated with septicemia hospitalization rates in the analyses for persons aged 50-64y, 65-74y, and 74-84y. Percent African Americans in a given age group was positively associated with septicemia hospitalization rates in the analyses for persons aged 75-84y and over 85y. Average minimal daily temperature was positively associated with septicemia hospitalization rates in the analyses for persons aged 18-49y, 50-64y, 75-84y and over 85y. Conclusions: Our results suggest positive associations between the rates of prescribing for penicillins and the rates of sepsis hospitalization in US adults aged 50-84y. Further studies are needed to understand the potential effect of antibiotic replacement in the treatment of various syndromes, such as replacement of fluoroquinolones by other antibiotics, possibly penicillins following the recent US FDA guidelines on restriction of fluoroquinolone use, on the rates of sepsis hospitalization.