The swelling of the right eye may be caused by the following: 1. Infection of the lid gland: The formation of acute inflammation of the lid gland, also called mydriasis, is the most common cause, usually caused by Staphylococcus aureus infection of the lid gland, or acute inflammation of the follicular gland at the root of the eyelashes and so on, manifesting as localized swelling and pain in the right eye, and clinical manifestations such as painful blinking and conjunctival congestion. If it is a right eye granuloma, anti-inflammatory treatment should be given in a timely manner. 2. Allergic reaction: The local skin of the right eyelid may have a local allergic reaction to the contact cosmetics or some other allergens, which may also cause swollen eyes and itchy skin. If you are allergic, you can apply local ice packs, and you can also use anti-allergy drops or eye ointment for treatment. 3, Other: There is also the possibility of conjunctivitis and keratitis, caused by inflammation of the conjunctiva and cornea, which can also increase eye discharge, burning sensation in the eyes, foreign body sensation, grinding pain, soreness, eye congestion and other clinical manifestations. In case of conjunctivitis or keratitis of the eye caused by infection, promptly treat the eye with symptomatic eye drops according to the causative organism.