A pharmaceutical composition comprising a combination of (A) (1S)-1,5-anhydro-1-[5-(4-ethoxybenzyl)-2-methoxy-4-methylphenyl]-1-thio-D-glucitol and (B) at least one member of the group consisting of insulin secretagogues, insulin sensitizers, insulins, dipeptidyl peptidase IV inhibitors, ±-glucosidase inhibitors, and GLP-1 mimetics, has superior efficacy in preventing or treating diabetes mellitus, diseases associated with diabetes mellitus, or complications of diabetes mellitus and yet it causes no appreciable side effects.
