Swollen feet after staying up late, in most cases the patient is in a sitting position, this situation usually indicates poor blood circulation in the lower extremities, mainly seen in some patients after lower extremity fracture surgery, or long-term smoking, accompanied by vaso-occlusive vasculitis of the lower extremities, and also seen in some patients with varicose veins or venous thrombosis. In this category of patients, poor vascular reflux in the lower extremities, prolonged sitting and staying up late lead to poor venous reflux, blood pooling around the tissues and exuding in the tissue spaces, resulting in obvious swelling, and of course, staying up late also has a certain impact on liver and kidney function, and patients with previous liver or kidney disease are more likely to have poor peripheral blood flow. If necessary, we should conduct relevant examinations to exclude some kidney disease or heart problems, and ask the patient to elevate the affected limb, pay attention to more sleep, and apply heat, massage and physical therapy to the swollen limb to help reduce the swelling.