Your Care Instructions: Styes and chalazia (say “chuh-LAY-zee-uh”) are both conditions that can cause swelling of the eyelid. A stye is an infection in the root of an eyelash. The infection causes a tender red lump on the edge of the eyelid. The infection can spread until the whole eyelid becomes red and inflamed. Styes… Continue reading Styes and Chalazia