An object of the present invention is to provide a formulation technique relating to an aqueous liquid preparation containing a water-soluble polymer and brimonidine and/or a salt thereof. An aqueous liquid preparation containing a water-soluble polymer, brimonidine and/or a salt thereof, and polyhexanide and/or a salt thereof can suppress a decrease in viscosity with time and, at the same time, reduce the viscosity of brimonidine and/or a salt thereof with time. It is possible to suppress the decrease in the content and provide excellent formulation stability. [Selection diagram] None
