Sjogren's syndrome is one of the most common autoimmune diseases in Taiwan. It is characterized by keratoconjunctivitis sicca and xerostomia. Although it is well established that Sjogren's syndrome is caused by infiltration and destruction of lacrimal gland and salivary gland by lymphocytic cells, effective treatment of patients' symptoms is lacking. Hydroxychloroquine is the most well-studied medication in Sjogren's syndrome. However, recent clinical trials showed disappointing effects of hydroxychloroquine in Sjogren's syndrome. Thus there is an unmet need to find effective treatment for patient's bothering symptoms.