Sjögren's syndrome is an autoimmune disease best described as a chronic inflammatory process characterised by decreased tear and saliva production. This results in dryness of the eyes and mouth known as the sicca complex (sicca means dry). Dryness of other mucus membranes of the body such as the intestines, lungs and reproductive system (especially the vagina in women) may also occur.

Sjögren's syndrome may occur by itself (known as Primary Sjögren's syndrome) or together with other autoimmune processes such as lupus, Rheumatoid Arthritis or other connective tissue diseases (known as Secondary Sjögren's syndrome).

Sjögren's syndrome was first described in Europe during the late 1800s and it was named after the Swedish ophthalmologist Henrik Sjogren. Sjögren's syndrome occurs in people of all races and it is a relatively common disorder. More than 90% of people with Sjögren's syndrome are women, with an average age of 50 years at time of diagnosis.