A pharmaceutical composition comprising a combination of (A) a 1-thio-D-glucitol compound represented by the general formula (I) and (B) at least one member of the group consisting of biguanides, insulin secretagogues, insulin sensitizers, insulins, dipeptidyl peptidase IV inhibitors, α-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.本發明關於一種包含下列者之組合的醫藥組成物：(A)以通式(I)代表的1-硫代-D-葡萄糖醇化合物：及(B)雙胍、促胰島素分泌劑、胰島素增敏劑、胰島素、二肽基肽酶IV抑制劑、α-葡萄糖苷酶抑制劑及GLP-1模擬劑中之至少一員，該醫藥組成物具有預防或治療糖尿病、與糖尿病有關之疾病或糖尿病併發症之卓越效力，且其到目前未引起可察覺的副作用。
