Abstract
Purpose: :
To investigate the retention of long-acting carteolol alginate ophthalmic solution on the human ocular surface using video meniscometry.
Methods: :
Twelve healthy volunteers with no external eye disease (9 male and 3 female; 37.7 yrs) were enrolled in this study. Fifteen microliters of 2% carteolol alginate ophthalmic solution were instilled into one eye of each subject and the same volume of standard 2% carteolol ophthalmic solution was instilled in the fellow eye, in a masked fashion. Before instillation and at 0, 2, 5, and 10 minutes after instillation, the central lower tear meniscus was monitored in each eye using a video meniscometer. The time-dependent change in the radius of the meniscus (R, mm) [ΔR(t) = R(t)-R(0)] was compared between both eyes of each subject. The change in the intraocular pressure (IOP, mmHg) and in the fluorescein breakup time (FBUT, sec) from baseline respectively to 30 and 60 minutes after the instillation were compared between both eyes.
Results: :
No significant difference was found in the reduction of IOP from baseline between eyes with carteolol alginate (3.0±1.1) instillation and with standard carteolol (2.4±1.4) instillation. No significant difference was found in the FBUT (before / after instillation) between eyes with carteolol alginate (4.6±2.4; 4.9±3.1) and with standard carteolol (4.3±2.6; 5.3±3.0). However, there was a significant difference in the change of the meniscus radius [ΔR(2); ΔR(5)] between eyes with carteolol alginate (0.12±0.11; 0.10±0.08) and with standard carteolol (0.04±0.07; 0.02±0.08) (p<0.05, respectively).
Conclusions: :
The present study suggests that the carteolol alginate solution can be better retained at the ocular surface than standard carteolol solution via not only the ionic interaction between alginic acid and carteolol but also the water retentive properties of alginic acid.
Keywords: drug toxicity/drug effects • cornea: tears/tear film/dry eye • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials