Hypoglycemia is a condition, in which blood sugar level falls below 70mg%. When blood sugar levels fall, there is an increase in counter-regulatory hormone levels to maintain the optimum blood glucose levels. In diabetics, hypoglycemia is very common among the Elderly, Debilitated patients, Patients with infections, Patients with impaired kidney function, Patients on insulin therapy, After alcohol abuse (or) vigorous exercise Psychological illness. Diabetics who fast for religious reasons or those with continuous vomiting are prone to hypoglycaemia. 1) It is more common in insulin-dependent diabetes than maturity onset diabetes (type II diabetes). Hypoglycemia is more common and pronounced if one aims for intense blood sugar control. 2) Hypoglycaemia can result in ECG changes with or without any symptom (silent ischemia). It also can trigger angina, heart attacks, acute heart failure and/or cardiac rhythm disturbances. 3) Some of the recent studies have shown that hypoglycemic episodes increase cardiovascular events and mortality. 4) Studies have also shown that adverse cardiovascular events are three times more common among those with intense glucose control compared with optimal control. Swings in blood sugar levels are equally hazardous. With the onset of hypoglycemia, heart rate and systolic blood pressure increase with vigorous heart pumping activity owing to adrenaline release. This may result in such symptoms as sweating, palpitations, giddiness, restlessness and confusion. Some patients may experience intense hunger and lack of concentration. Rarely can hypoglycemia be silent without any symptoms. The exact incidence of hypoglycaemia is not known because these episodes may be mild, moderate or severe. Mild symptoms may even be undetected. Mild hypoglycemic events are more common but less reported. Patients, who experience frequent hypoglycaemic episodes, may take corrective steps with the onset of premonitory symptoms. Dead in the bed syndrome due to nocturnal hypoglycemia resulting in cardiac rhythm disturbances has been thought to be due to extreme hypoglycaemia, and fortunately this is very rare. The challenge of physicians is to adjust blood glucose levels to near normal range and reduce complications of diabetes, while at the same time minimize or prevent hypoglycaemic events. One must particularly be more cautious in diabetics with underlying heart disease. Blood Hba1c level is a biochemical parameter to assess long term glucose control. Hypoglycaemic episodes are more common if Hba1c level is 7%.