3. Foreign objects
Another very common cause of keratitis is the presence of a foreign object in the eye. Eyelashes, hair, makeup, dirt, dust, and even small rocks or pieces of bark; these are just some examples of the foreign objects that can enter your eye. The eyeballs are extremely delicate, and therefore, when a foreign object makes its way inside of them, the cornea can become scratched or otherwise damaged.
A scratched cornea can become inflamed and infected, which leads to keratitis. If you have recently discovered that a foreign object has entered your eye, try flushing the object out immediately. Run clean, lukewarm water over your eye; doing so can help to expel whatever has become lodged within it and reduce your chances of developing keratitis. If, however, you are experiencing redness, irritation, pain, light sensitivity, and swelling, your cornea may be inflamed; prompt medical care is essential.