Stye is an acute inflammation of an eyelash follicle and its (external or internal) sebaceous gland, almost always caused by Staphylococcus Aureus.
Stye is a very common infection arising with: redness of the eyelid rim, pain, heaviness of the eyelid.
A yellowish little spot often appears on the edge of the inflamed eyelid and it usually ruptures on its own with the outflow of pus and the relieve of the pain sensation. The internal stye causes the same symptoms but it is not straightly visible because it is located on the eyelid inner wall.
The treatment for the stye consists in the application of a warm-wet compress, aimed at favouring the rupture on its own, and topical antibiotics (in association with anti-inflammatory drugs or not) according to the recommendations of the Ophthalmologist. Seldom it is required the drainage of the stye by a surgical excision.