Hello. The dosage of Metformin is upto 2000mg per day i.e. 4 tablets of 500mg taken at intervals of 6 hrs. However, I have seen adverse effects like fullness of stomach and dyspepsia, heartburn and other gastrointestinal symptoms with this dosage of Metformin in my practice. Hence, I donot prescribe more than 1500mg per day. You are also on a combination of Losartan and Hydrochlorothiazide - which are medications for high blood pressure. Long standing and uncontrolled hypertension can cause kidney dysfunction. Metformin should not be taken in case of kidney problems. Please check your kidney function periodically. You have not mentioned whether 140 is your fasting or after meals blood sugar. If it is fasting, then it is high and needs to be controlled. In that case, your diabetologist will review your diet and lifestyle habits and if necessary add another anti-diabetic medicine in addition to Metformin. If it is your after meals blood sugar, then you need not worry, it is normal. Keep checking your HbA1c levels once every 3 months as it gives the average blood sugar levels over the past 3 months. Rest of your medications can be continued. Hope this helps. Regards, Dr Geeta