The stye is an infection of the implantation area of an eyelash called the “pilosebaceous follicle. It presents itself as a small, red, hot and painful bulge the size of a grain of barley located on the edge of the eyelid and centred on one eyelash. It appears within a day or two then when it ripens, it forms a pocket of visible white-yellowish pus on the surface of the stye.