This observational research study is to better understand patients with eosinophilic esophagitis (EoE) who have recently been prescribed DUPIXENT® (dupilumab). The purpose of this research study is to look at how DUPIXENT is used in normal care of patients with EoE. Possible benefits to others include a better understanding of EoE and helping to inform research and clinical trial design leading to treatment decisions in this patient population going forward. Patient questionnaires will measure the following: * How EoE makes one feel * EoE symptoms * How EoE affects quality-of-life * How EoE impacts aspects of daily life * How difficult it is to swallow * How EoE symptoms have changed throughout the study