Obstructive jaundice, urine color is dark yellow, obstructive jaundice patients due to high jaundice in the blood, will lead to higher bilirubin in the urine, bilirubinuria, urine will appear dark yellow phenomenon. Patients taking oral vitamin B12 may also experience dark yellow urine, and when taking oral dysentery for dysentery, patients may experience dark yellow urine when urinating. Obstructive jaundice is most commonly associated with choledochal stones or choledochal tumors. When a patient develops choledochal obstruction, it can lead to elevated bilirubin in the blood and bilirubin in the urine, resulting in bilirubinuria and dark yellow urine.