What Are the Side Effects of Metformin?
Metformin's most common side effect is stomach upset, usually diarrhea, but sometimes also vomiting and nausea. Taking metformin in the middle of a meal may help lessen this side effect. This side effect may also lessen over time, and some women find that particular foods trigger more stomach upset than others.
More serious side effects associated with metformin are liver dysfunction and a rare, but extremely serious side effect, lactic acidosis. While taking metformin, your doctor should monitor your kidney and liver functions. People with heart, liver, kidney, or lung disease should not take metformin. Be sure to provide your doctor with a thorough medical history.
The use of metformin to treat infertility related to PCOS is still being researched, and different doctors have opposing views on if, when, and how to use metformin to treat infertility. Don't be afraid to voice your concerns and questions to your care provider, so that together, you can decide if this treatment is for you.
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