Disclosed herein are pharmaceutical compositions comprising an aqueous solution of a 7-dimethylamino tetracycline antibiotic and a divalent or trivalent cation, preferably a magnesium cation, wherein the molar ratio of divalent or trivalent cation to the 7-dimethylamino-tetracycline antibiotic is greater than 2:1 and wherein the solution does not comprise a pharmaceutically acceptable oil, has a pH greater than 4 and less than 7, and is suitable for intravenous administration. Also disclosed are water soluble solid compositions which upon dissolution have these properties and methods and kits for producing such compositions.
