People with diabetes are more prone to dry eyes. If your eyes feel tired, sore or gritty or sandy, you may have 'dry eyes', or 'blepharitis', or both.

The eyelids have tiny glands in them, especially the lower lids. These glands make substances that mix with tears, and help the tears to spread across the eye. This thin layer of tears lubricates the eyes, stops them drying out, and keeps them comfortable. However, as you get older, and particularly if you have dry skin, these glands can block. As a result the glands do not make the chemicals that enables the tears to  spread evenly across the front of the eye. The tears break up and dry patches develop on the surface of the eye which makes them feel sore.

Dry eyes is a common problem for diabetics. The eyes may feel scratchy or gritty, as though there is something in them. They also be a little itchy or feel as though they are burning, with crusting, as though there is something in them (foreign body sensation). Additionally, your lashes may crust up and your eye lids may stick.

Blepharitis is the medical term for inflamed eyelids. The inflammation is like eczema of the skin, with red, scaly eyelids. This makes the eyes feel tired and particularly uncomfortable in sunlight or a smoky atmosphere. They may also be slightly red.

Blepharitis is not usually a serious condition but it is always wise to consult a doctor.  Some simple eye care such as cleaning the eye lids or replacing the tears with a lubricant such as Clinitas Soothe can make the eyes feel more comfortable.

A useful animation which explains this is available on this NHS hospital site.