CHOOSING THE BUFFER SYSTEM FORMULATION FOR EYE DROPS WITH TETRAHYDROZOLINE HYDROCHLORIDE

Abstract

The purpose of this article is developing the optimal formulation of excipients for eye drops with tetrahydrosoline hydrochloride and researching of the locally irritating effect of the selected formulation of eye drops. The objects of the research are experimental solutions of eye drops with tetrahydrosoline hydrochloride using different combinations of excipients. Evaluation of test results in the selection of the formulation was performed according to the physico-chemical parameters of the prepared eye drops solution along with researching of stability. Assessment of the local irritation was performed on Chinchilla rabbits, particularly on the mucous membrane of the rabbit’s eye. The optimal formulation of the eye drops with tetrahydrozoline hydrochloride of a medicinal product using citrate buffer solution was developed.  The result solution represents a clear homogeneous aqueous solution to physical and chemical properties.  The developed formulation contains (in grams): tetrahydrozoline hydrochloride - 0.05; benzalkonium chloride - 0.01; disodium edetate - 0.01;  sodium chloride - 0.84; citrate buffer - to a pH of 6.2 to 6.5;  injection water - up to 100 ml. Samples of the experimental series of eye drops meet the requirements of HFC on ophthalmic drugs in terms of physico-chemical quality indicators as description, transparency, osmolality, pH of the solution, quantitative content of tetrahydrazoline hydrochloride. The results obtained in the research of stability of the eye drops experimental series throughout a long-term and accelerated storage during 6-months observation indicate the invariance of critical quality indicators, such as description, transparency, pH of the solution and the quantitative content of tetrahydrazoline hydrochloride. The results of determining the locally irritant effect on the mucous membrane of the rabbit’s eye showed that developed formulation of the eye drops does not cause any local irritation, neither visual reaction from the mucous membrane of the eye. The damaging effect level was 0 points in comparison with the other drugs. It is proved that the proposed formulation of eye drops meets the requirements of SPhU, stable and comfortable to use. The results of this experiment have a practical importance for development of new generic drugs.