Sudden swelling of the left eye bag is usually not uremia, which has more causes and needs to be clarified through examination. Uremia is usually characterized by loss of appetite, indigestion, etc. In severe cases, oral eruption, tongue inflammation, vomiting blood, blood in stool, etc. Combined with biochemical and renal ultrasound examinations, the diagnosis can be clarified. Sudden swelling around the eyelids and eye bags may be due to acute blepharitis or skin allergy. Allergic reactions caused by exposure to certain substances, such as pollen and dust from plants, or prolonged late nights and exposure to electronic products, can be triggering factors. In addition to swelling around the eyelids and bags, the patient may also experience redness of the surrounding skin, pain when touched, itching, etc. The diagnosis should be confirmed at the ophthalmology department through a slit lamp examination. In addition, this condition may be caused by excessive rubbing of the eye area, which generally requires no treatment and observation. People with swollen left eye bags need to pay attention to not rubbing the eyes, do not eat seafood, do not eat spicy and stimulating food, do not drink too much water before going to bed, so as not to aggravate the swelling.