Sjögren's syndrome is a disorder in which the mouth and eyes become extremely dry. Sjögren's syndrome is often associated with other autoimmune disorders (a condition in which the body's immune system mistakenly begins treating parts of the body as foreign invaders). While the immune cells should attack and kill invaders like bacteria, viruses, and fungi, these cells should not attack the body itself.

There are three types of Sjögren's syndrome. Primary Sjögren's syndrome occurs by itself, with no other associated disorders. Secondary Sjögren's syndrome occurs along with other autoimmune disorders, like systemic lupus erythematosus, rheumatoid arthritis, scleroderma, vasculitis.

When the disorder is limited to involvement of the eyes, with no other organ or tissue involvement evident, it is called sicca complex.

Women are about nine times more likely to suffer from Sj...