Metformin is among the most commonly prescribed drugs in the world. It’s very effective in regulating blood sugar levels for people living with type 2 diabetes.
However, metformin is also increasingly being prescribed for people who live with polycystic ovary syndrome (PCOS).
This article will cover everything you need to know about using metformin for PCOS.
Why would someone with PCOS be prescribed metformin?
Polycystic ovary syndrome (PCOS) is the most common hormonal issue affecting young women.
PCOS can cause you to miss your period or experience irregular periods, struggle with fertility, and can cause excess hair growth, acne, and weight gain. Metformin is increasingly used to treat the symptoms of PCOS.
Metformin comes in many brands and is taken daily (or two times each day) typically as an oral pill.
If you have PCOS, you might be prescribed metformin because it has been shown to stabilize hormone levels and because it helps many women get back to regular menstrual cycles.
There is also evidence that the longer you take metformin, the more regular your cycle will become and the less serious many of the symptoms of PCOS may become.
If you have PCOS and have struggled with weight gain, irregular periods, acne, or infertility, your doctor or medical provider may prescribe you metformin to manage these symptoms.
Is metformin safe to use for PCOS?
Metformin is broadly accepted as a safe medicine, no matter the reason it is prescribed for you.
It is important to note, however, that metformin for the treatment of PCOS is not officially approved by the Food and Drug Administration (FDA). Any prescribing by a physician to treat PCOS with metformin will be prescribed as “off-label”.
There is a risk of side effects that you should be aware of when taking the drug for PCOS.
The most common side effects of metformin include gastrointestinal symptoms such as nausea, vomiting, and diarrhea.
These symptoms tend to be mild, and most doctors will recommend taking the medication with a meal to reduce the severity of these GI symptoms. Your doctor or medical care team may also recommend starting with a low dose of metformin and gradually increasing the dose over time to make sure you don’t experience serious upset stomach or other side effects.
There are also very rare – and more serious – side effects such as lactic acidosis, which is an increase in lactic acid in the blood. It’s much more likely to occur in people with kidney or liver problems, so your doctor will likely ask you about your medical history before prescribing metformin.
Long-term use of metformin is also known to increase the risk of vitamin B12 deficiency for some people, so supplementation or bloodwork is sometimes recommended.
Metformin has also not undergone rigorous clinical trials in pregnant and breastfeeding women, although there is an evidence base to expect it would be effective.
If you are trying to conceive and have PCOS, your doctor may prescribe metformin for you off-label because it can help to restore regular menstrual cycles and ovulation. It’s important to discuss whether it’s safe to continue taking the drug if and when you become pregnant.
Can PCOS go away with metformin?
Unfortunately, polycystic ovary syndrome is a chronic condition without a known cure. However, the symptoms of PCOS can be managed by medications, including metformin.
Metformin works by reducing insulin resistance, which is a common symptom of PCOS. By improving insulin sensitivity, metformin can help to regulate menstrual cycles, reduce symptoms such as hirsutism (excess hair growth) and acne, and improve fertility.
While metformin can be an effective treatment for managing the symptoms of PCOS, it is important to note that it is not a cure for the condition. Women with PCOS may need to continue taking metformin or other medications to manage their symptoms over the long term.
Lifestyle changes like eating a healthy, balanced diet and getting regular exercise can also help manage the symptoms of PCOS.
If you have PCOS, it’s important to work with your doctor or medical provider to develop a plan of care that works for your health history, minimizes symptoms, and meets your goals.
How exactly does metformin help people with PCOS?
To understand how metformin can people with PCOS, it’s important to understand some of the biological changes that occur with PCOS.
While the underlying cause or “trigger” for PCOS isn’t well understood, researchers do know that PCOS involves a series of interrelated changes occurring between the ovaries, the pancreas, insulin levels, and the body’s sex hormones (among other hormones).
All of these complex hormonal changes cause the ovaries to develop extra follicles or cysts (the “cysts” in “polycystic”) and insulin resistance. Insulin resistance leads to higher blood sugars and taxes the pancreas as it has to try to produce more insulin to bring the body’s blood sugar down to a normal level.
Metformin works in several different ways at once, many of which can help with the symptoms of PCOS.
Metformin lowers the amount of sugar produced by the liver, decreases sugar absorption in the intestines, and allows individual cells in the body to consume more sugar and use that sugar more efficiently.
Together, these three changes decrease the amount of sugar (in the form of glucose) circulating in the bloodstream. This allows the body to become more insulin sensitive, which means the pancreas has to make less insulin in the first place.
These changes can lead to more regular menstrual cycles, reduce sex hormone imbalances, and can help reduce both acne and hirsutism (excess hair growth, particularly on the chest and face) that occur with PCOS.
Large clinical trials also demonstrate that metformin helps people lose weight they might have gained from PCOS.
Frequently asked questions
Metformin dosages for the treatment of PCOS will vary, and a doctor is more likely to start you on a lower dose at first (e.g., 500 mg with a meal) to manage adverse side effects of the drug, like nausea and upset stomach.
Meta-analysis has shown that 1,500 mg – 2,550 mg per day is generally sufficient to address the major symptoms of PCOS.
But as with all prescription drugs, your doctor can evaluate your health goals and history, as well as any underlying symptoms you’re experiencing to determine the right starting dose.
Studies have not definitively proven any way to prevent PCOS. However, the symptoms of PCOS can be reduced or managed through medications (including metformin) and through living a healthy lifestyle, including maintaining a balanced diet and getting enough exercise.
While the drug is generally safe and often effective, metformin unfortunately doesn’t work for everyone with PCOS.
Metformin is highly effective in reducing blood sugar levels for women with PCOS.
Most – though not all – women also experience significant improvements in acne and unwanted sex hormone-associated hair growth.
While many women also see their periods become more regular with the use of metformin, only about 40% will experience “totally normal” menstruation.
Metformin’s weight loss effects also vary significantly from person to person.
Metformin needs time to build up in the body. Oftentimes, your doctor will start you on a lower dose of the drug in order to avoid uncomfortable GI side effects.
Most people will see improvements in their blood sugar levels after a few weeks. However, long-term studies of metformin’s use for PCOS show that it may take as long as 6 months for the drug to establish regular menstruation.