Swelling under the eyes of patients can be seen in normal people, but also may be blepharitis, eye allergies and other factors caused by the patient should consult a doctor in a timely manner to clarify the cause of the disease after treatment. 1. Physiological conditions: If a normal person drinks a lot of water before going to bed or cries for a long time, the patient may appear to have a swollen eye, usually without special treatment, after resting can appear to be gradually relieved. 2. Blepharitis: Blepharitis refers to purulent inflammation of the eyelid glands, mostly caused by staphylococcal and other bacterial infections, and patients may experience redness, swelling, pain, burning and other symptoms. 3. Eye allergy: allergic patients can have an allergic reaction when exposed to pollen, hair and other allergens, patients can have eyelid swelling, eyelid itching and other uncomfortable symptoms. Patients should detach themselves from the allergens and use anti-allergy drugs such as loratadine when necessary. It is recommended that patients with significant eyelid swelling consult a physician for evaluation of their condition and treatment as prescribed by the physician.