The invention relates to an aqueous composition comprising in combination an alkyl pyrrolidone, such as a C8-C18 linear alkyl pyrrolidone, and an alkyl polysaccharide such as an alkyl polyglucoside, and a method of .enhancing the efficacy of an enzyme containing composition for use in cleaning medical instruments comprising the step of including in said composition an alkyl pyrrolidone and an alkyl polysaccharide. The methods and compositions of the present invention may further include at least one enzyme such as proteases, lipases, amylases, and cellulases.