Most corneal ulcers are caused by infections and can be bacterial (common in people who wear contact lenses), viral herpes simplex virus and varicella virus, or fungal (improper care of contact lenses or overuse of eye drops that contain steroids).
Symptoms include red eyes, pain, feeling like something is in the eye, tearing, pus/thick discharge, blurry vision, pain from bright lights, swollen eyelids, or a white or gray round spot on the cornea.
Self-treatment consists of removing contact lenses, applying a cool compress to the affected eye and washing hands often.
Anyone with a corneal ulcer should be seen immediately by an ophthalmologist, who will do testing and most likely prescribe antibiotic and other eye drops. If the ulcer persists or worsens, a surgical procedure known as corneal transplantation may be performed.