PURPOSE: Evaluate the effects of 0.1% diclofenac and 0.03% flurbiprofen on corneal sensitivity in normal canine eyes after repeated dosing and 30 days of twice daily dosing
METHODS: A prospective, randomized, masked, crossover study of 18 healthy, non-brachycephalic dogs was performed. For Phase I, the study drug was instilled every five minutes for five doses, and corneal sensitivity of the
... [Show full abstract] control and treated eye was evaluated prior to drug instillation and every 15 minutes post-instillation for 60 minutes. For Phase II, the study drug was instilled every 12 hours for 30 days, and corneal sensitivity for the control and treated eye was evaluated prior to drug instillation on days 0 and 30. A washout period of at least 30 days occurred between drug crossover and between phases. Temperature and humidity were measured throughout data collection.
RESULTS: Average age and weight were 5.7 ± 3.3 years and 25.1 ± 6.8 kg, respectively. There were no significant differences in corneal sensitivity after multiple instillations of diclofenac (P=0.67) or flurbiprofen (P=0.54). Corneal sensitivity was also not significantly different after 30 days of twice daily use with either diclofenac (P=0.82) or flurbiprofen (P=0.56). Decreasing humidity was associated with an increase in corneal sensitivity measurements (P=0.004).
CONCLUSIONS: Neither diclofenac nor flurbiprofen have an effect on corneal sensitivity in normal canine eyes after repeated dosing or 30 days of twice daily dosing. Ambient humidity may have an effect on corneal sensitivity measurements with a longer filament length eliciting a blink response at a lower humidity.
