PCOS: Insulin and Metformin

Teens with PCOS may have elevated insulin levels and are more likely to develop diabetes. Metformin is a medication often prescribed for people with PCOS to help prevent or treat diabetes. A lifestyle that includes healthy nutrition and daily exercise is an important part of a PCOS treatment plan.

What is insulin?

Insulin is a hormone made by an organ in the body called the pancreas. The food you eat is broken down into simple sugar (glucose) during digestion. Glucose is absorbed into the blood after you eat. Insulin helps glucose enter the cells of the body to be used as energy. If there’s not enough insulin in the body, or if the body can’t use the insulin, sugar levels in the blood become higher.

What is insulin resistance?

If your body is resistant to insulin, it means you need high levels of insulin to keep your blood sugar normal. Certain medical conditions such as being overweight or having PCOS can cause insulin resistance. Insulin resistance tends to run in families.

What can insulin resistance do to me?

High insulin levels can cause thickening and darkening of the skin (acanthosis nigricans) on the back of the neck, axilla (under the arms), and groin area. In teens with PCOS, high insulin levels can cause the ovaries to make more androgen hormones such as testosterone. This can cause increased body hair, acne, and irregular or few periods. Having insulin resistance can increase your risk of developing diabetes.

How can I lower my insulin levels?

You can help lower your insulin levels naturally by eating fewer starches and sugars, and more foods that are high in fiber and low in refined carbohydrates. Low glycemic foods, on the other hand, don’t raise your blood sugar or insulin levels as much as foods that are high in sugar or refined carbohydrates. Exercising is another way to improve your PCOS. Fitting in 60 minutes of exercise each day is recommended, but any amount of exercise you do will help manage your PCOS. Exercise decreases insulin resistance.

What else will lower my insulin level?

Metformin (also known as Glucophage®) helps to regulate the amount of glucose (sugar) in your blood. It makes your body more sensitive to insulin, and decreases the amount of glucose your liver releases. Young people with high insulin who take Metformin are less likely to develop type 2 diabetes than those who don’t take a medication that lowers insulin. Research studies have shown that young people with PCOS who are overweight and who were treated with Metformin and a healthy lifestyle (healthy nutrition and regular exercise) were able to lose weight and lower their fasting blood sugar. Taking Metformin and maintaining a healthy weight also improves cholesterol levels. Metformin is not approved by the FDA (Food and Drug Administration) for PCOS, but it is commonly prescribed for adolescents with impaired glucose tolerance.

How do I take Metformin?

Metformin is available as a pill or liquid. It is usually taken 2–3 times a day with your meals (usually breakfast and dinner). Your health care provider will tell you to begin at a very low dose and slowly increase the amount of medicine you take over a few months—”start low, go slow.” Your health care provider may prescribe once a day long acting (XR–extended release) Metformin instead. It’s important that you take this medication exactly as prescribed by your health care provider. Do not break, chew, or crush the pills. Be sure to swallow the whole pill(s).

How do I store Metformin?

Keep your Metformin tightly closed, in the same bottle it came in. Do not remove the label on the bottle. Store it at room temperature away from high temperatures and any moisture. Do not store Metformin in the bathroom. Be sure to keep your medicine away from young children.

Are there any reasons not to take Metformin?

People with kidney or liver problems should not take Metformin. Your health care provider will check your blood to make sure that you do not have blood, kidney or liver problems before you start Metformin and then usually once a year after that. If you get sick and throw up or have diarrhea, call your health care provider and stop your Metformin until you feel completely well. It’s very important not to be dehydrated (not having enough fluids in your body) while taking Metformin. You should not binge drink alcohol and take Metformin. Also, if you’re going to have surgery or a medical or dental procedure where you can’t have anything to eat or drink, talk to your health care provider about stopping the Metformin for 48 hours before the procedure. If you’re scheduled for an X–ray that includes a “contrast material” (a dye that helps the radiologist see the images better), you should talk to your health care provider about stopping your Metformin for up to 48 hours before and after the test. Getting dehydrated, having kidney problems, or having a serious infection can cause the rare condition called “lactic acidosis”, so it’s important to talk to your health care provider about any of these problems.

Does Metformin have any side effects?

In general, healthy young people don’t experience many side effects. About a third of people who take Metformin have stomach upset such as nausea, diarrhea, gas, and loss of appetite. Some people may complain of a metallic taste. If the side effects are a problem for you, it’s important to talk with your health care provider. You may be able to lower your dose for a few days and slowly build back up to your regular dose.

What if I miss a dose of my Metformin?

When you first start taking Metformin, it’s a good idea to ask your health care provider what to do if you miss a dose. Write down the answer so you will have a plan if it happens. In general, you will probably be told NOT to take the pills that you missed, especially if it’s almost time for your next dose. Never double up on pills to make up for a missed dose.

Can I get pregnant while taking Metformin?

Yes. If you’re sexually active and you’re not taking oral contraceptive pills or using another method of birth control, it’s possible that you’ll have menstrual cycles and ovulate (release an egg). If your egg is fertilized (sperm from a male comes together with an egg of a female), you could become pregnant. People with PCOS are more likely to get pregnant while taking Metformin. You should talk with your health care provider about a method of birth control that’s right for you.

Important things to remember when taking Metformin:

• If you’re prescribed Metformin for PCOS, be sure to tell your health care provider and pharmacist about all the prescription medications and over–the–counter medicines that you’re taking.
• If you’re having surgery, including dental surgery, tell your health care provider or dentist that you’re taking Metformin for PCOS. Ask when you should stop taking it before the procedure.
• Metformin can lower your body’s ability to absorb certain vitamins (B12 and folate), so it’s a good idea to take a multivitamin (with B vitamins).
• Alcohol can be dangerous while taking Metformin. You’re more likely to get dehydrated or develop liver problems. If you have 3–4 drinks at a time, Metformin is not a good treatment option for your PCOS. Ask your health care provider about other treatment options or decrease your use of alcohol.
• If you’re sexually active, be sure to talk with your health care provider about taking the oral contraceptive pill or about using another reliable birth control method.
• Talk to a dietitian about planning meals and snacks that are PCOS–friendly.
• Try to fit in about 60 minutes of exercise every day.
• Keep all of your medical appointments and be sure to go for any lab tests that your health care provider might order.

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Our health guides are developed through a systematic, rigorous process to ensure accuracy, reliability, and trustworthiness. Written and reviewed by experienced healthcare clinicians from Boston Children's Hospital, a Harvard Medical School teaching hospital and consistently ranked as a top hospital by Newsweek and U.S. News & World Report, these guides combine clinical expertise, specialized knowledge, and evidence-based medicine. We also incorporate research and best practices from authoritative sources such as the CDC, NIH, PubMed, top medical journals, and UpToDate.com. Clinical specialists and subject matter experts review and edit each guide, reinforcing our commitment to high-quality, factual, scientifically accurate health information for young people.