lacrimal gland

The lacrimal gland is a tear-producing gland that is located in the upper eyelid, underneath the orbital bony ridge (i.e., under the bone that makes the upper eye socket).  Most people think that the lacrimal gland is the main source of tears. Actually, that’s not quite true.  Most of the tears that cover our eyes are made by small accessory glands that cover the entire conjunctiva (the skin over the white of the eye) and under the eyelids.  These little glands continuously excrete tears and create our “basal tear rate.” The lacrimal gland is mostly responsible for reflexive tearing … the tears that come out when crying or when the eyes are irritated. Many people with chronically dry eye complain that their eyes seem to water all the time.  For these people, their basal tear rate is low so their eyes dry out and “sting” a little bit.  This stinging causes the lacrimal gland to reflexively dump out all its tears at once, leading to episodes of excessive watering followed by periods of relative dryness. By breaking this dry-wet cycle with regular use of artificial tears, the lacrimal gland can calm down and decrease these unnecessary tearing episodes.