Provided is concentrated aqueous azithromycin formulation from about from about 2%-20%, and a method of making a concentrated aqueous azithromycin formulation which includes preparing and sterilizing a first solution comprising a strong base to form a sterilized solution, dissolving the azithromycin in an aqueous solution comprising an acid consisting essentially of a strong acid, and adding the aqueous solution comprising the strong acid to the sterilized solution comprising the strong base. The strong acid has a pKa less than about &minus1.74 and the method is carried out without addition or use of a weak acid.
