Dry eye syndrome (DES) is a highly prevalent ocular condition inducing an inflammatory response on the ocular surface. Common symptoms include ocular discomfort, visual impairment and instability of the tear film with potential damage to the ocular surface.

In addition, an intact tear film is important to provide a smooth optical surface, to act as a barrier to pathogens, to nourish the epithelial cells of the ocular surface and to prevent exsiccation. Alterations in the tear film composition, which can have their origin in several conditions, lead to tear film hyperosmolarity or instability resulting in DES.

Regardless of the cause of DES, chronic dryness of the ocular surface leads to an increased susceptibility to oxidative stress, which is triggered by reactive oxygen species (ROS). This results in cell damage and activation of the immune system, keeping up inflammatory processes . In order to prevent ROS damage, several micronutrients such as vitamin C, E, and certain carotenoids, omega-3 free fatty acids, flavonoids and minerals have been used because of their antioxidant capacities.

Based on this knowledge the potential of these antioxidant dietary supplements has been discussed as a treatment option for DES. Preliminary data support the hypothesis that antioxidant supplementations, in particular, supplementation with omega 3 fatty acids may be beneficial for patients with DES.

The purpose of the present study is to test the hypothesis that treatment with dietary supplements improves subjective and objective symptoms of DES.

Inclusion Criteria:

• Men and women aged over 18 years
• History of dry eye syndrome for at least 3 months
• Tear Break Up Time (BUT) < 10 seconds or Schirmer I test < 7 mm
• At least 2 symptoms of dry eye syndrome (foreign body sensation, burning, photophobia, blurred vision, pain, itching)
• -Normal ophthalmic findings except dry eye syndrome

Exclusion Criteria:

• Participation in a clinical trial in the 3 weeks preceding the study
• Symptoms of a clinically relevant illness in the 3 weeks before the first study day
• Presence or history of a severe medical condition that will interfere with the study aim as judged by the clinical investigator
• Wearing of contact lenses
• Intake of dietary supplements in the 3 months preceding the study
• Glaucoma
• Treatment with corticosteroids in the 4 weeks preceding the study
• Topical treatment with any ophthalmic drug except topical lubricants in the 4 weeks preceding the study
• Ocular infection or inflammation
• Ocular surgery in the 3 months preceding the study
• Sjögren's syndrome
• Stevens-Johnson syndrome
• Pregnancy, planned pregnancy or lactating