Eosinophilic esophagitis (EoE) is an increasingly diagnosed, immune-mediated disease characterized by inflammation of the esophagus in both children and adult, causing significant morbidity. Adults typically present with dysphagia and a history of food impaction. Diagnosis should be considered in patients with histological evidence of eosinophilia (≥15 eosinophils per high-power field) on esophageal biopsy. More recently, it has been observed that a significant percentage of patients with esophageal eosinophilia respond both clinically and histologically to PPI therapy. This disorder has been named PPI-responsive esophageal eosinophilia (PPI-REE). Recent studies suggest that patients with PPI-REE have similar clinical and endoscopic features of patients with EoE. Specifically, both PPI-REE and EoE patients have a strong disposition to allergy compared to patients without eosinophilia. As such, PPI-REE may represent a subset or variant of EoE. Effective treatment of EoE requires a multidisciplinary approach with gastroenterologists, pathologists, allergists, and nutritionists. Treatments include elimination and elemental diets, topical glucocorticoids (fluticasone and budesonide), and endoscopic dilation.