From the Guidelines
A stye is primarily caused by a bacterial infection, typically Staphylococcus aureus, that affects an oil gland or hair follicle, leading to a painful, red bump. This condition can be compared to furunculosis, which is the presence of an infected hair follicle, as described in the study 1. The infection often occurs when oil glands become clogged with dead skin cells, debris, or excess oil, creating an environment where bacteria can multiply. Key factors that increase the risk of developing a stye include poor hygiene, such as touching the eyes with unwashed hands or not removing eye makeup properly. Other risk factors may include chronic blepharitis (eyelid inflammation), rosacea, diabetes, and a weakened immune system. Most styes heal on their own within a week with simple home care like warm compresses applied for 10-15 minutes, 3-4 times daily, as the body's immune system fights off the infection. It is essential to avoid wearing contact lenses or eye makeup during the healing process to prevent further irritation or infection. If a stye persists beyond a week, grows very large, affects vision, or spreads to other areas, it is crucial to consult a doctor who may prescribe antibiotic ointments or oral antibiotics for severe infections, as seen in the treatment of furunculosis which includes local heat, incision and drainage, or systemic antibiotics that cover S aureus, the most common causative agent 1. Never attempt to pop a stye, as this can spread the infection and lead to more severe complications.