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Signs metformin is working

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Signs it's workingSigns it's not workingHow long it takesOther optionsSummary
Metformin is a common medication to help treat type 2 diabetes. It can start to take effect within 3 hours but may take around 1 week to show signs that it’s working.
Medically reviewed by Jennie Olopaade, PharmD, RPH
Written by Suan Pineda
Updated on

Metformin is one of the most common drugs to treat type 2 diabetes. Doctors can also prescribe it to people at high risk of developing the condition, and it can also help people with type 1 diabetes.

The medication helps balance your blood sugar levels by improving how insulin works, reducing the amount of sugar the liver makes, and lowering how much sugar the intestines absorb.

As with other medications to treat chronic conditions, it may take time to work and may not be suitable for everybody.

Knowing the signs that metformin is and isn’t working can help you feel confident in the management of your condition.

Need a refill for metformin (Glucophage)? You may be able to get an online prescription through Optum Perks in as little as 15 minutes with no video or appointment needed. Learn more here.

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Signs metformin is working

An hourglass sand timer sitting on a table representing the time it takes and signs metformin is working.
Vera Lair/Stocksy United

Metformin is available under brand names like Glucophage and Glumetza. It is one of the main medications for type 2 diabetes, a condition that affects about 37 million people in the United States.

The main sign that metformin is working is that your blood sugar levels will be lower. You can tell this by frequently checking your levels using a home test kit.

You’ll also find that your A1C levels become stable. A1C refers to the amount of hemoglobin, a substance in your blood that has glucose attached to it. To check your A1C levels, you can take an A1C test, also known as the HbA1c test.

This means you should stop feeling symptoms of high blood sugar (hyperglycemia). This can mean:

  • feeling more energetic because your body is using insulin more effectively
  • having to pee less often
  • not feeling as thirsty or hungry as before 

Signs it’s not working

The main sign that metformin isn’t working is when your blood sugar levels are not getting lower. This means you might continue to experience hyperglycemia. The main signs that the medication isn’t working include:

  • frequent peeing
  • high A1C levels
  • fatigue and tiredness
  • increased thirst and hunger
  • blurry vision

Talk with a healthcare professional if you keep experiencing these symptoms while taking metformin. They may consider switching medications or suggest other ways to manage blood sugar levels, including lifestyle measures.

How long does it take for metformin to work?

How long it takes to see results from metformin depends on the person and the medication type — it comes in both immediate-release and extended-release formulations. The immediate-release form will start to work faster than the extended-release version.

Metformin usually takes around 3 hours to get to work after taking it. But this doesn’t mean you’ll notice its effects right away. Some people can start to experience results very quickly, while some older 2006 research suggests that most notice a change within 1 week of treatment, regardless of the type of metformin. 

Metformin alternatives

Metformin may not be suitable for everyone. Doctors do not usually recommend it to people with heart, liver, and kidney failure. It’s also not recommended for people who are allergic to metformin. But these people can use it with caution if a doctor decides the benefits outweigh the risks.

Metformin can also cause side effects that some people may not tolerate, such as:

  • constipation
  • diarrhea
  • bloating
  • chest pain
  • rash

There are other medications and lifestyle measures that can help treat type 2 diabetes. Medications include:

Taking medications is just one of the ways to manage blood sugar levels when you have diabetes. But just as important is practicing certain lifestyle measures that can help manage diabetes symptoms and benefit overall health. These include:

  • maintaining a moderate weight
  • exercising regularly, about 150 minutes of physical activity a week
  • eating a balanced diet that’s low in refined carbs
  • reducing stress
  • avoiding smoking and alcohol

If you need help covering the cost of medications, the free Optum Perks Discount Card could help you save up to 80% on prescription drugs. Follow the links on drug names for savings on that medication, or search for a specific drug here.

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Metformin is one of the most common medications to treat type 2 diabetes. Available under the brand names Glucophage and Glumetza, it helps lower blood sugar levels by improving the efficiency of insulin, decreasing the amount of glucose the liver produces, and reducing the amount of sugar the intestines absorb.

The main sign of metformin working is lower blood sugar levels. You can monitor this by testing your levels regularly and being aware of the symptoms of higher blood sugar. Metformin is working when you notice a reduction in hunger, thirst, and urination frequency. This usually takes about 1 week.

But metformin may not be suitable for everyone, like people with heart, liver, and kidney failure and those who are allergic to the drug. Other medications are available to help lower blood sugar levels.

Lifestyle measures are also important to help manage diabetes. This can involve taking regular exercise and following a balanced diet. 

Talk with a healthcare professional if metformin doesn’t seem to be lowering your blood sugar levels or if it’s causing side effects that are difficult to manage. A doctor may be able to prescribe alternative medications.

Download the free Optum Perks Discount Card to save up to 80% on some prescription medications.

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