Blepharitis is inflammation of the eyelids which causes them to become red and swollen. It commonly occurs when the oil glands located near the base of the eyelashes becomes clogged.
This is quite a common condition, accounting for about 1 in 20 eye problems reported. It's not serious, but it can lead to other conditions like dry eye syndrome.
The cause of blepharitis is not known although it's not an infection, it can be caused by a reaction to the bacteria that live naturally on the eyelid skin. It is however more common if you have a skin condition such as:
Blepharitis can develop at any age but it is more common in people over 50. It is not a serious condition although it can lead to further problems especially for people also suffering from dry eye syndrome - click here for more information on this condition.
It is a condition that can appear and then be followed by periods with no symptoms.
Please note: It's not possible to catch blepharitis from someone else who has it.