Diabetic patients have an increased risk of coronary insufficiency and of complications following percutaneous angioplasty, with or without stent. In particular, the risk of restenosis is increased, although it can be significantly reduced by the use of drug-eluting stents. Various systemic pharmacological approaches have also been evaluated to reduce the risk of restenosis after coronary angioplasty, with or without stent, but with only mitigated effects. The aim of the present paper is to describe the effects of antidiabetic agents on the risk of restenosis, the need of new revascularisation procedures and the incidence of major cardiac events (death, non fatal myocardial infarct, revascularisation). The authors successively analyse the effects of metformin, insulin and thiazolidinediones (glitazones). These latter agents have shown the best protective effect although, paradoxically, they are the most controversial because of cardiovascular safety issues in the management of type 2 diabetes.