Thank you for your query Mr.Sivakumar. As per the information provided, you are 57yrs old, diabetic for 9 yrs, presently on oral anti-diabetic agent (ISTAMET 50/1000), with a fasting blood sugar of 120mg% and post prandial of 190mg%. I would like to enquire about your HbAic level to assess your long term control of blood sugar. Istamet is an oral anti diabetic agent, which is composed of Sitagliptin 50mg Metformin 1000mg. Both these drugs have a comparitively safe profile in diabetes mellitus. Metformin, belongs to a group of drugs called biguanides and Sitagliptin belongs to DPPVI inhibitors. These drugs are beneficial in that they do not cause hypoglycemia (low blood sugar level) and are weight neutral (metformin may help in weight reduction). Hence the unwanted side effects are prevented. Coming to the side effects. The commonest side effect of metformin is Gastrointestinal intolerance, like nausea and diarrhea. In case this occurs some dose reduction may be needed. It should be used with caution in those with renal impairment (raised creatinine level, more than 1.5mg%), and it can cause lactic acidosis. Sitagliptin can also cause nausea and rhinitis in some. A rare but important side effect of this drug is Pancreatitis. Any pain upper abdomen or discomfort occurring after taking this drug must be brought to the notice of your physician. Some dose reduction is required in renal impairment. You can safely continue these drugs, if you are not developing intolerable side effects. Since, you are long term diabetic, please get your renal function test and Urine for ACR tested at least once a year. If there is a renal dysfunction noted, these drugs may need dose adjustment. Hope this helps you. Regards Dr. Ayusmati Thakur