Common causes of redness, swelling and pain at the corners of the eyes include granuloma, blepharitis, dacryoadenitis, etc. Treatments include medications such as antibiotics and surgical treatments. 1. Eyelid swelling: Eyelid swelling is an acute purulent inflammation of the eyelid, mainly caused by staphylococcal infection. Inflammation of granuloma can lead to hard nodules with pressure and pain in the eyelid, and swelling and pain in the corner of the eye when the inflammation spreads to the corner of the eye. Treatment includes medication such as levofloxacin eye drops, erythromycin eye ointment, etc., and surgical incision can be made to drain pus if an abscess forms. 2. Blepharitis: Blepharitis is a subacute or chronic inflammation of the skin of the eyelid margins, eyelash follicles and their glands, which can lead to redness, swelling and pain in the eyes when the body is infected and caused by inflammation. Treatment includes localized cleansing and medication such as tobramycin drops and levofloxacin. 3. Dacryoadenitis: Dacryoadenitis is a general term for inflammatory diseases caused by bacteria and other microorganisms as well as various factors, and patients often show symptoms such as redness and swelling of the upper eyelids, conjunctival congestion, and increased secretions. Commonly used medications include indomethacin, ofloxacin, prednisone, etc. The appropriate medication needs to be selected under the guidance of a doctor. When patients experience discomfort, they should go to the hospital immediately.