The patient’s eyelid swelling may be caused by mosquito bites, or it may be caused by chalazion or blepharitis. 1. Mosquito bites: Unilateral swelling of the right upper eyelid may be caused by mosquito bites, in which case soap and water can be applied to the upper eyelid to relieve the itch. 2. Chalazion: Chalazion is a common cystic disease of the eyelid, caused by the blockage of the blepharoplasty gland and the accumulation of glandular secretions, the patient’s eyelid may appear elevated swelling. Patients can use hot towels to apply warm compresses to the eyes to speed up the absorption of the cysts. Surgical excision can also be used to remove the eyelid swelling. 3. Eyelid swelling: Eyelid swelling is an acute infectious inflammation that occurs in the glands of the eyelid, and the patient mainly manifests as redness, swelling, and pain in the eyelid unilaterally. Patients with swollen eyelids are advised to seek prompt medical attention to assess their condition and follow the doctor’s instructions for treatment.