Ophthalmic preparations are directly used for the treatment of ocular effects of sterile preparation, its safety is one of the most important quality attributes. Bacteriostatic agents, also known as preservatives, most ophthalmic formulations contain bacteriostats, the purpose is to prevent repeated use after opening, preservation process of microbial contamination. However, most of the antimicrobial agents have a certain toxicity and irritation. Therefore, the ocular toxicity of the ophthalmic bacteriostats was studied. It is one of the important tasks in the research and development of ophthalmic preparation to regulate the addition and use of these agents, to find new antibacterial agents for ophthalmic preparations, and to minimize the clinical adverse reactions caused by antibacterial agents.
Benzalkonium Chloride (BAC) is one of the most widely used antibacterial agents for ophthalmic preparations. It is used in ophthalmic preparations listed in Europe, America, Japan and other countries. Approximately 70% use BAC as a bacteriostat. Its safety and effectiveness are recognized, commonly used concentration of 0.004% to 0.02%.
Polyquatemium-1 (Polyquatemium-1, PQ-1), also known as chlorine chloride, Alcon is the development of a new bacteriostatic agent, trade name POLYQUAD. PQ-1 in the 20th century, the early 90's for contact lens care solution. And is used as a bacteriostatic agent for ophthalmic preparations, and its usual concentration is 0.001%. PQ-1 is considered to be less toxic, the effect of a new generation of good ophthalmic formulations bacteriostats. Because of its late application, only a few ophthalmic formulations are currently available, such as IZ-BA, Tears Naturale, Systane Ultra, Of the patented product. Therefore, the safety of PQ-1 remains to be further studied and evaluated.