Medications, hormonal influences, autoimmune conditions, and thyroid metabolism perturbations can all cause dry eye.

“there's obviously lots of medications that do it through cholinergic side effects absolutely but think about all the antihistamines you know hormonal influences are profound in terms of dry eye anything that causes dry mouth can also cause dry eye in that sense autoimmune conditions can cause dry eye so sjogren's rheumatoid arthritis all of the connective tissue diseases have a dry eye component to them perturbations of thyroid metabolism cause dry eye”