Behçet's disease is a chronic inflammatory disease that affects the blood vessels and is manifested by recurrent mouth and genital ulcers, eye inflammation, and skin changes.[1] Intestinal involvement is a rare but serious form of this disease, with symptoms similar to inflammatory bowel disease and complicating diagnosis and treatment.[1] In the presented case of a 23-year-old patient with intestinal Behçet's disease, colonoscopic examination revealed circumferential ulceration, mucosal edema and narrowing of the ileocecal lumen.[1] The patient was initially treated with infliximab (an anti-TNF drug), which produced only partial improvement and later lost efficacy.[1] After switching to upadacitinib, a Janus kinase (JAK) inhibitor, there was complete resolution of symptoms and mucosal healing at subsequent endoscopy.[1] This case suggests that JAK inhibitors such as upadacitinib may be a promising alternative for patients with intestinal Behçet's disease unresponsive to anti-TNF drugs.[1] The use of therapeutic monitoring of drug levels allows for personalized treatment adjustments and potentially improves long-term outcomes in complex cases.[1]