Eosinophilic oesophagitis is a complex multifactorial disorder and one of the leading causes of dysphagia in children and adults. An allergen-mediated inflammatory response is the underlying cause of this disease. Allergen-activated Th₂ cells, eosinophils and interleukins 4, 5 and 13 play a major role in the pathogenesis of eosinophilic oesophagitis. Difficulties swallowing, especially dry food, and the related increase in chewing time, as well as episodes of oesophageal food impaction, often requiring endoscopic treatment, are the leading symptoms. Children develop nausea, vomiting, abdominal pain, irritability and reluctance to consume foods. The incidence of eosinophilic oesophagitis has increased dramatically in recent years and is now estimated at approximately 42.2/100,000 per year in adults. Endoscopy followed by histopathological examination of at least six biopsy specimens taken from two different sections of the oesophagus is the gold diagnostic standard. The eosinophilic oesophagitis endoscopic reference score (EREFS) is used for endoscopy and the eosinophilic oesophagitis histologic scoring system (EoE HSS) is used for histopathology to objectify the assessment. Pharmacological and dietary therapies are of primary importance in eosinophilic oesophagitis. Proton pump inhibitors and glucocorticoids are most commonly used. Allergen-free diets significantly contribute to the achievement of permanent histological and clinical remission. In the case of permanent oesophageal remodelling, endoscopic and/or surgical treatment should be considered.