A stye, medically known as a hordeolum, is a small lump that appears on, inside or under the eyelid or on eyelashes. Styes typically result from a staphylococcal bacteria infection or from a clogging of the oil glands around the eyelashes or inside the eyelid, but can be triggered during times of stress. They are usually harmless, despite their appearance – causing redness, tenderness, pain and sometimes light-sensitivity and eye-watering.

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