What are the potential side effects of metformin use over a long period of time?

 Metformin is generally considered safe and well-tolerated when taken as prescribed. However, like all medications, it can cause side effects, especially when taken for a long time. Some of the potential side effects of metformin use over a long period of time are:

1. Vitamin B12 deficiency: Taking metformin for a long time can cause vitamin B12 deficiency, which can make the patient feel very tired, breathless, and faint
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2. Gastrointestinal problems: Metformin can cause gastrointestinal problems such as diarrhea, nausea, vomiting, and flatulence
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3. Lactic acidosis: Although rare, metformin can cause a serious condition called lactic acidosis, which is a buildup of lactic acid in the blood. This condition can be life-threatening and requires immediate medical attention
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4. Decreased vitamin B12 serum concentration: Metformin can cause decreased vitamin B12 serum concentration, which can lead to anemia and other health problems
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5. Unusual muscular pain: Metformin can cause unusual muscular pain, which can be a sign of a serious side effect
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6. Decreased appetite: Metformin can cause decreased appetite, which can lead to weight loss
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7. Anxiety and depression: Metformin can cause anxiety and depression in some patients
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In summary, metformin can cause several potential side effects when taken for a long time, including vitamin B12 deficiency, gastrointestinal problems, lactic acidosis, decreased vitamin B12 serum concentration, unusual muscular pain, decreased appetite, and anxiety and depression. If any of these side effects occur, the patient should consult their doctor immediately.