To compare the efficacy, safety and tolerability of 0.05% topical cyclosporin eye drop to Refresh in moderate to severe dry eye patients. Null hypothesis is: there is no difference between these two groups.

Inclusion criteria:

1. Participants are moderate to severe dry eye patients aged more than 18 years of age
2. Oxford staining scores of more than five.
3. OSDI scores of more than 0.1

Outcome measurements:

Main parameter is staining score (corneal + conjunctival) Other parameter is OSDI score, symptom of ocular surface discomfort score, number of daily artificial tear needed, TBUT, Schirmer I score, cytokines level & markers Safety parameters: VA, IOP, cyclosporin level

Inclusion Criteria:

• moderate to severe dry eye

Exclusion Criteria:

• lid anomaly, previous CsA use