Long term complications continue to be the major source of morbidity and mortality in patients with diabetes. Acarbose could potentially help to reduce diabetic complications if it improved glucose control, reduced lipid levels and hyperinsulinaemia. Acarbose has been shown to effectively reduce postprandial hyperglycaemia and haemoglobin A1c. This effect might be helpful in patients with insulin-dependent diabetes mellitus, as insulin injections do not provide complete control of rises in postprandial glucose levels, and in patients with non-insulin-dependent diabetes mellitus, because it simplifies the treatment programme. If improved control is shown to reduce complications, acarbose may be helpful. Although acarbose does not reduce hyperinsulinaemia, it reduces lipid levels and thus could reduce the risk of atherosclerosis.