Unexplained gastrointestinal bleeding associated with Upadacitinib: A Case Report.

Upadacitinib, a selective Janus kinase (JAK)-1 inhibitor, is widely prescribed for moderate-to-severe rheumatoid arthritis. Although generally well tolerated, rare gastrointestinal adverse events have been reported. We describe a 48-year-old woman who presented with syncope following coffee-ground vomiting and melaena while taking Upadacitinib 15 mg daily. Endoscopic investigations, including oesophagogastroduodenoscopy, colonoscopy, and capsule endoscopy, revealed no active bleeding or identifiable lesions. Laboratory findings showed severe anaemia (haemoglobin 5.3 g/dL) with normal liver and coagulation profiles. Following discontinuation of Upadacitinib and transfusion of four units of packed red cells, her haemoglobin improved to 9 g/dL and remained stable at 13 g/dL during three- and six-month follow-up. This case highlights a possible association between Upadacitinib and unexplained gastrointestinal bleeding, emphasising the importance of clinician awareness, early drug withdrawal, and prompt reporting to pharmacovigilance systems.