45b326c5_Chart___Joslin_Diabetes_Center__3
[0] Biguanides Metformin (Glucophage) Metformin liquid ( Riomet) Metformin extended release (Glucophage XR, Fortamet, Glumetza) [1] Metformin: usually taken twice a day with breakfast and evening meal. Metformin extended release: usually taken once a day in the morning. [2] Decreases amount of glucose released from liver. [4] Always tell healthcare providers that it may need to be stopped when you are having a dye study or surgical procedure. [3] 
Bloating, gas, diarrhea, upset stomach, loss of appetite (usually within the first few weeks of starting). Take with food to minimize symptoms. Metformin is not likely to cause low blood glucose. In rare cases, lactic acidosis may occur in people with abnormal kidney or liver function.
Oral Diabetes Medications Chart | Joslin Diabetes Center
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