The purpose of this study is to investigate safety and therapeutic efficacy of antihistamine (desloratadine) on inflammation and disease activity when administered as adjuvant therapies with the traditional therapy 5-aminosalisylic acid (mesalamine) in patients with mild to moderate ulcerative colitis.

Ulcerative colitis is a chronic inflammatory autoimmune disease affecting the colon. The World Health Organization has classified it as a relatively new treatment-resistant disease, and its prevalence has reportedly increased significantly in Egypt. A preclinical study was conducted to evaluate desloratadine as a potential therapeutic agent for ulcerative colitis, based on its known anti-inflammatory and antioxidant properties. The study concluded that desloratadine effectively alleviated experimental ulcerative colitis. This positive effect is attributed to its anti-inflammatory and antioxidant properties, which work by regulating mast cell activity and inhibiting histamine release.

Inclusion Criteria:

• Both male and female sex.
• patients with age ranged from 18 to 65.
• patients with active mild and moderate ulcerative colitis according to American College of Gastroenterology (ACG) Clinical Guideline.
• Patients treated with 5-aminosalisylic acid (mesalamine).

Exclusion Criteria:

• Patients with severe UC
• Significant liver or kidney function abnormalities
• Pregnant or lactating females
• Treatment with systemic or rectal steroids
• Treatment with immunosuppressant or biological therapies
• Known allergy to desloratadine or any ingredient in the formulation
• Patients with other inflammatory diseases
• Patients with history of colon cancer
• Patients with complete or partial colectomy