Type II diabetes is a heterogeneous disease where environment and genetics are 
important factors for the expression of the disease. The high cost for treating 
complications of diabetes is a burden for public health systems and governments 
worldwide. Type II diabetes has been causing debilitation worldwide for many 
decades, and a single drug that safely treats the disease has yet to be 
discovered. Sulfonylureas, biguanides, alpha-glucosidase, meglitinides, DPP-4 
inhibitors and thiazolidinediones are among the classes of oral hypoglycemic 
drugs available to treat Type II diabetes, but concerns exist regarding safety 
and efficacy of these drugs. In this article we present the pros and cons of the 
six classes and discuss some of the latest advances towards the development of 
new drugs for the treatment of Type II diabetes.