Blepharitis occurs because of a dysfunction of the oil glands (meibomian glands) that are present along the eyelid margins.
The meibomian glands are responsible for producing an oily substance that makes up part of your tears. A problem in these glands can lead to excess production of this oily substance or a blockage in the glands, which can cause the eyelids to become irritated and inflamed.
Blepharitis is often caused by bacterial infection. Everyone has bacteria on the surface of their skin, but in some people, bacteria thrive in the skin at the base of the eyelashes. Large amounts of bacteria around the eyelashes can cause dandruff-like scales and debris to form along the lashes and eyelid margins.
Eyelid inflammation (blepharitis) is a common condition especially among Asians. Risk factors include dandruff, dry skin, acne, diabetes or poor hygiene.