Mediterranean and Low-Histamine Diets for Pediatric Chronic Spontaneous Urticaria

Chronic spontaneous urticaria (CSU) is a chronic inflammatory skin disease that can substantially impair quality of life in children and adolescents. Pharmacological treatment may not adequately control symptoms in all patients, increasing interest in dietary interventions. This randomized controlled trial aims to compare the effects of a Mediterranean diet and a low-histamine diet, in addition to standard medical treatment, on disease activity, disease control, and quality of life in pediatric patients aged 12-18 years with chronic spontaneous urticaria. Participants will be allocated to one of three groups: standard treatment alone, standard treatment plus a low-histamine diet, or standard treatment plus a Mediterranean diet. The dietary intervention will last four weeks, with follow-up through eight weeks.

Inclusion Criteria: * Age 12-18 years. Confirmed diagnosis of Chronic Spontaneous Urticaria (CSU) according to international guidelines. No recent use of systemic corticosteroids or immunosuppressive therapy (except short-term acute use). Written informed consent provided by both the participant and a parent/legal guardian. Exclusion Criteria: * Presence of a neurodevelopmental disorder. Presence of any other known chronic disease. Presence of a disease requiring a special therapeutic diet. Presence of an acute infection. Presence of any food allergy. Recent use of systemic corticosteroids, biologic agents, immunosuppressive therapy, or high-dose antihistamines (except short-term acute use).