Transparent eye drops containing latanoprost
An object of the present invention is to provide better formulations of a latanoprost ophthalmic solution. The present invention provides a clear ophthalmic solution comprising latanoprost as an active ingredient and benzalkonium chloride as a preservative wherein white turbidity due to a change of formulation is prevented by at least one means selected from the following 1) to 3); 1) adding a surfactant, 2) using benzalkonium chloride represented by the formula of [C 6 H 5 CH 2 N(CH 3 ) 2 R]Cl (wherein R is alkyl having 12 carbon atoms) as the preservative and 3) adding a nonionic tonicity agent as a tonicity agent.
1. A clear ophthalmic solution comprising (i) latanoprost having a concentration of 0.005% (W/V), (ii) 0.003 to 0.01% (W/V) of benzalkonium chloride represented by the formula of [C 6 H 5 CH 2 N(CH 3 ) 2 R]C1, wherein R is an alkyl group having 12 carbon atoms and (iii) at least one pharmaceutically acceptable carrier selected from the group consisting of crystalline sodium dihydrogenphosphate sodium chloride, diluted hydrochloric acid and sodium hydroxide.
2. A method of preventing white turbidity in an ophthalmic solution comprising latanoprost having a concentration of 0.005% (WV) and at least one pharmaceutically acceptable carrier selected from the group consisting of crystalline sodium dihydrogenphosphate, sodium chloride, diluted hydrochloric acid and sodium hydrogen, the method comprising adding to said solution 0.003 to 0.01% (W/V) benzalkonium chloride represented by the formula [C 6 H 5 CH 2 N(CH 3 ) 2 R]C1, wherein R is an alkyl group having 12 carbon atoms.