The swelling of the bags under the left eye needs to be treated according to the specific causes (such as physiological causes, trauma, blepharitis, mosquito bites and allergies, etc.), including general treatment, medication, surgical treatment and so on. 1. Physiological causes: poor sleep quality and crying can cause physiological swelling of the bags under the eyes, patients need to adjust their work and rest in a timely manner, and can relieve the swelling and improve the discomfort by applying hot compresses locally on the eyes. 2. Pathological causes (1) eye trauma: trauma caused by the bags under the eyes, early patients can first local cold compresses, after 48 hours, patients can be local hot compresses, to promote the swelling subside. (2) blepharitis: blepharitis patients in the inflammation stimulation, there can be eyelid redness and swelling, there can also be burning sensation of the eye and other discomforts, the patient can follow the doctor’s instructions to use erythromycin ointment treatment, to control inflammation, to relieve the discomfort of the eye. (3) Mosquito bites: after mosquito bites, the patient’s eyelids may appear itching, swelling and other discomforts, the patient can follow the doctor’s instructions to use glycerine lotion or antihistamines such as loratadine, cetirizine, etc., to relieve the discomfort of the eyes. (4) eye allergy: eye allergy patients may appear eye swelling, may also be accompanied by itching and other discomforts, patients need to be detached from the allergens, follow the doctor’s instructions to use anti-allergy drugs, such as loratadine. It is recommended that patients with swollen eyes should consult a doctor in time to assess their condition and follow the doctor’s instructions for treatment.