The effects of bimatoprost and unoprostone isopropyl on the intraocular pressure of normal cats
Abstract
Objective: To evaluate the effects on intraocular pressure (IOP), pupillary diameter (PD), blepharospasm score, conjunctival injection score, and aqueous humor flare score when either 0.03% bimatoprost solution is applied once daily or 0.15% unoprostone isopropyl solution is applied twice daily topically to the eyes of normal cats. Materials and methods: The aforementioned parameters were evaluated daily in each of 12 cats throughout the entirety of the study. During an initial 10-day treatment phase a single eye of six of the cats was treated with 0.03% bimatoprost solution while a single eye of the remaining six cats was treated with buffered saline solution (BSS) once daily. During a second 10-day treatment phase a single eye of six of the cats was treated with 0.15% unoprostone isopropyl solution while a single eye of the remaining six cats was treated with BSS twice daily. Contralateral eyes of all cats remained untreated at all time points. Results: Blepharospasm score, conjunctival injection score, and aqueous humor flare score never rose from a value of 0, for any eye of any cat during the study. The mean ± SD of IOP for eyes treated with 0.03% bimatoprost solution and BSS were 16.55 ± 3.06 mmHg and 18.02 ± 3.52 mmHg, respectively. The mean ± of PD for eyes treated with 0.03% bimatoprost solution and BSS were 5.7 ± 1.57 mm and 6.39 ± 1.78 mm, respectively. The mean ± SD of IOP for eyes treated with 0.15% unoprostone isopropyl solution and BSS were 15.7 ± 2.91 mmHg and 17.2 ± 2.9 mmHg, respectively. The mean ± SD of PD for eyes treated with 0.15% unoprostone isopropyl solution and BSS were 5.8 ± 1.43 mm and 6.9 ± 1.37 mm, respectively. There was no significant difference (P ≥ 0.05) in IOP or PD between eyes treated with 0.03% bimatoprost solution vs. eyes treated with BSS. Similarly, there was no significant difference (P > 0.05) in IOP or PD between eyes treated with 0.15% unoprostone isopropyl solution vs. eyes treated with BSS. Conclusion: Neither once daily topical administration of 0.03% bimatoprost solution nor twice daily topical administration of 0.15% unoprostone isopropyl solution significantly affect the IOP of normal cats. Both 0.03% bimatoprost solution and 0.15% unoprostone isopropyl solution induced no significant ocular side effects in normal cats when dosed over a 10-day treatment period. © 2005 American College of Veterinary Ophthalmologists.