Off-Label Uses of Metformin
Though the FDA has only approved metformin to treat type 2 diabetes, the medication may provide a host of other health benefits for people with or without diabetes. Griebeler says that it’s currently being used off-label to help treat obesity, PCOS and related fertility challenges, and weight gain caused by antipsychotic medications, as well as to prevent diabetes.
Obesity When people who don’t have diabetes but are overweight take metformin, the medication helps with weight loss, says Dr. Besser. “I have used [metformin] for obesity management — for some with normal sugars, some prediabetic — and it helps,” she says. “It’s not a miracle cure, but it does seem to help.” She says to expect only a modest 10 to 15 pounds of weight loss, but she adds that that progress could inspire people to stay on track with their goals. “It’s enough to kick-start things. For anyone who’s quite overweight, any weight loss is encouraging. It makes them want to keep going,” says Besser.
What’s more, people who are overweight or have obesity who also navigate knee osteoarthritis may experience a noticeable reduction in related pain when taking metformin.
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PCOS Metformin can be a helpful component of a PCOS treatment plan, improving the body’s insulin sensitivity, which can then support overall hormone balance, healthy menstrual cycles, and fertility. And for women with PCOS who become pregnant, there’s some evidence that metformin may lower their risk of early pregnancy loss and preterm birth.
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“Diabetes doesn’t cause PCOS, but people with PCOS have a higher risk of developing diabetes,” says Besser. She’s used metformin to treat people with PCOS, including a couple of people who managed to become pregnant after they started taking it.
Medication-Related Weight Gain Metformin also appears to be an effective pharmacological treatment of antipsychotic-induced weight gain, which is commonly experienced among people who take medications for psychiatric diseases like schizophrenia.
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Diabetes Prevention Alongside healthy lifestyle interventions, metformin can be an effective therapy for reducing higher-risk individuals’ likelihood of developing type 2 diabetes. It appears particularly helpful for people who are overweight or have obesity but don’t have diabetes.
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Long COVID Metformin may also play a role in treating long COVID, a range of health problems that may persist or develop after a COVID-19 infection. In fact, people who receive early outpatient COVID-19 treatment with metformin may reduce their risk of developing long COVID by as much as 41 percent.
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