Thomas Chen1, Cynthia C Powell2. 1. Department of Small Animal Clinical Sciences, C247 Veterinary Medical Center, University of Tennessee, Knoxville, TN, 37996, USA. 2. Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, 300 W. Drake Rd., Fort Collins, CO, 80523, USA.
Abstract
OBJECTIVE: To determine the effect of once daily topical 0.3% naltrexone (NTX) on tear production, tear film breakup time (TFBUT), and corneal sensitivity in dogs with uncontrolled keratoconjunctivitis sicca (KCS). ANIMALS STUDIED: Sixteen dogs with uncontrolled KCS. PROCEDURES: A randomized placebo-controlled trial was performed in 16 dogs with topical 0.3% NTX once daily or topical saline solution drops once daily. A baseline was obtained at week 0 for tear production (Schirmer tear test 1 and 2-STT1, STT2), TFBUT, and corneal sensitivity. STT1, STT2, and TFBUT were then subsequently measured at weeks 1, 2, and 4 while on NTX or saline drops. Corneal sensitivity measures were repeated at week 4. The drops were subsequently discontinued and all parameters rechecked at week 5. RESULTS: There was no statistically significant difference in tear parameters or corneal sensitivity between the NTX-treated and the saline-treated groups. CONCLUSION: Topical 0.3% NTX given as a once daily dose over 4 weeks did not alter tear production, tear film stability, or corneal sensitivity in dogs with uncontrolled KCS.
OBJECTIVE: To determine the effect of once daily topical 0.3% naltrexone (NTX) on tear production, tear film breakup time (TFBUT), and corneal sensitivity in dogs with uncontrolled keratoconjunctivitis sicca (KCS). ANIMALS STUDIED: Sixteen dogs with uncontrolled KCS. PROCEDURES: A randomized placebo-controlled trial was performed in 16 dogs with topical 0.3% NTX once daily or topical saline solution drops once daily. A baseline was obtained at week 0 for tear production (Schirmer tear test 1 and 2-STT1, STT2), TFBUT, and corneal sensitivity. STT1, STT2, and TFBUT were then subsequently measured at weeks 1, 2, and 4 while on NTX or saline drops. Corneal sensitivity measures were repeated at week 4. The drops were subsequently discontinued and all parameters rechecked at week 5. RESULTS: There was no statistically significant difference in tear parameters or corneal sensitivity between the NTX-treated and the saline-treated groups. CONCLUSION: Topical 0.3% NTX given as a once daily dose over 4 weeks did not alter tear production, tear film stability, or corneal sensitivity in dogs with uncontrolled KCS.