Oral omega 3 in different proportions of EPA, DHA, and antioxidants as adjuvant in treatment of keratoconjunctivitis sicca in dogs

ABSTRACT Purpose: To compare the efficacy of 0.03% topical tacrolimus in combination with oral omega (ω) 3 with different ratios of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and antioxidants as adjuvant in the treatment of keratoconjunctivitis sicca (KCS) in dogs. Methods: Forty-five dogs with KCS were evaluated monthly for 6 months. Evaluations included performance of the Schirmer tear, fluorescein, and lissamine green tests. Tear film break-up time (TBUT) was assessed. Conjunctival cytology was evaluated at the beginning, middle, and end of the study. Conjunctiva was biopsied at the beginning and end of the study. Dogs were randomly assigned to one of the three groups (n=15): Group T (topical tacrolimus 0.03%), Group TO (topical tacrolimus + ω-1.5 EPA: 1 DHA), or Group TOA (topical tacrolimus + ω-1 EPA:4.5 DHA + antioxidants). Results: There was a significant improvement in clinical signs in all groups. TBUT increased throughout treatment in all groups; this effect was most pronounced in Group TO. Cytological analysis performed at the end of the study period, showed decreased levels of lymphocytes, neutrophils, and metaplastic and squamous cells in Groups T, TO, and TOA. Histological analysis performed at the end of the study period showed decreased levels of lymphocytes and neutrophils and increased levels of goblet cells. These effects were most pronounced in Group TO. Conclusion: Oral treatment with ω-3 containing a higher proportion of EPA than DHA increased the effectiveness of topical tacrolimus 0.03% in the treatment of keratoconjunctivitis sicca in dogs.