In the beginning, there may not be any symptom. When blood sugar is above 180 mg%, sugar starts appearing in the urine. Sugar in the urine drags water and you pass a lot of urine and feel dry and thirsty. You may also feel tired and lose weight. Your appetite increases and peculiarly you may notice that you are losing weight in spite of eating more. Chance of infection is higher if you have high sugar and also your healing from infection, cut or wound may be unusually delayed. Some people complain of poor eyesight.