Production risk from live weight variation of market pigs has become a more important concern in U.S. swine production. Packers are concerned about the variation in carcass size because of the demand for standardized cuts and the use of automation in the slaughter process. Swine producers care about standardized pigs because of revenue implications and possible links to animal health and productivity. Pig size variation can be due to various condition and inputs including antibiotics. However, discussions on risk reduction from antibiotic use have generally not been considered. Our work extends previous studies by systematically examining the aspects of production risk reduction and highlights the potential results of banning antibiotics from a risk perspective. Using data from National Animal Health Monitoring System 2000 survey data and PigCHAMP, we identify the relationship between antibiotic use and production risk by an econometric model. Applying production costs for feeder to market pigs and a price matrix, the uncertainty in profits is evaluated. The impacts of risk on the decision making of swine producers are examined under the framework of expected utility and stochastic dominance analysis. Our results show that production risk from weight variability of market hogs is important in determining profits and utility under a pricing system. Production risk (i.e. weight gain variability) is related to the use of sub-therapeutic antibiotics. Swine producers could decrease production risk and enhance utility by adjusting antibiotic use. These results offer some support for optimal use of sub-therapeutic antibiotics.