An inflamed gland in the eyelid margin. Annoying, but almost always harmless.

In a stye a hair follicle or gland at the lid margin is inflamed. In a chalazion an oil gland is blocked and walled off. Both are more common with blepharitis.
Contact your GP or the out-of-hours GP service (huisartsenpost) straight away if you have:
This page is a short summary and does not replace a consultation. Want to know how the eye works? See The eye.