[A comparative study of the ocular tolerance of 3 timolol-based preparations: the influence of preservatives on ocular tolerance].
OBJECTIVE
Ophthalmic preparations can cause toxic ocular reactions, often associated with the use of preservatives. The aim of this study was to compare the ocular tolerance of three ophthalmic preparations based on timolol: a preservative free ophthalmic preparation (Timabak) and two other commercially available preserved preparations (Timoptol) and Timoptol LP).


METHODS
The effect of repeatedly instilling eye drops for 28 days on rabbit eyes was assessed in vivo by mean of a confocal laser scanning ophthalmoscope. The corneal microlesions were selectively marked by fluorescein.


CONCLUSIONS
The overall results show the good ocular tolerance of the three tested products. However, a closer comparison between the products brought out differences in the extent of lesions among the tested products depending on their composition. Indeed the preservative free eye drops appeared better tolerated than the two preserved preparations.
Section de Pharmacie, Institut de Chimie Thérapeutique, Université de Lausanne, CH-1015 Lausanne, Suisse.
P
P
Furrer
J
J
Berger
J M
JM
Mayer
R
R
Gurny
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000633:toxicity*; D000818:Animals; D009883:Ophthalmic Solutions; D011817:Rabbits; D013999:Timolol / Q000008:administration & dosage / Q000633:toxicity*
D000319:Adrenergic beta-Antagonists; D009883:Ophthalmic Solutions; D013999:Timolol