Green J et al. - Use of sitagliptin in conjunction with the insulin-sensitizing medication metformin has been shown to decrease HbA1c levels more significantly than does either drug alone. This combination of medications is generally well tolerated, with no adverse effects on weight and a very low likelihood of treatment-related hypoglycemia. Use of both drugs will positively affect many of the underlying metabolic abnormalities associated with type 2 diabetes, including the disordered secretion of insulin and glucagon as well as impaired sensitivity to insulin which are known to accompany this disease.