Recent studies suggest the efficacy of family-based treatment (FBT) among youth with anorexia nervosa (AN) in intensive treatment settings. This study aimed to assess weight outcomes in youth who received an FBT intervention while hospitalized for medical complications of AN. Parental self-efficacy among participating caregivers was also measured. Post-discharge weights of 49 participants were compared with weights of 44 youth who were hospitalized prior to the provision of the FBT intervention. Youth who received the FBT intervention gained significantly more weight than youth in the retrospective treatment as usual group at 3 and 6 months following discharge. FBT youth were 2.84 times more likely than retrospective treatment as usual youth to achieve at least 95% of treatment goal weight at 6 months post-discharge. Finally, parental self-efficacy significantly increased in caregivers who participated in the FBT intervention. Findings provided preliminary support for the provision of FBT to medically hospitalized youth with AN.