INFLAMMATORY
- Allergic conjunctivitis
- Chronic blepharitis
- Systemic autoimmune disease (Sjogren's, SLE)
- Sarcoidosis
- Pemphigoid or Stevens-Johnson syndrome
NON-INFLAMMATORY
- Age-related dryness
- Dry environment
- Abnormal lipid component of tears
- Xerophthalmia (vitamin A deficiency)
- Impaired eyelid or lacrimal gland function
- Systemic or topical medication