Sudden or recurring styes can be caused by an overgrowth of bacteria from clogged oil glands. This is known as blepharitis. Blepharitis can develop when you don’t keep your eyelids clean and ...

Although not serious or dangerous in themselves recurrent styes interfere with vision and ... is usually only made once all other possible causes of tiredness have been excluded.

Source: Focus Medica. A small red, painful lump in the edge of the eyelid. Stye is usually caused by bacterial infection. It may be present inside or outside the eyelid on one or both eyes and is ...