Ozempic vs. Metformin: Comparing the Two Diabetes Medications

Ozempic (semaglutide) is a once-weekly injection used primarily for treating type 2 diabetes. This medication is well known for lowering blood sugar levels.

Metformin is an oral tablet that has been used for many years to treat high blood sugar levels in people with type 2 diabetes. It is considered a first-line therapy to lower blood sugar in newly diagnosed individuals.

Ozempic and metformin have a few differences, including their mechanisms of action (how they work), dosage forms, and availability. Although both medications can be used for diabetes, healthcare providers will often prescribe metformin at the start of therapy for the majority of patients.

This article will discuss the similarities and differences between Ozempic and metformin, including their uses, how they work, dosages, and implications for weight loss.

Person with obesity administering Ozempic injection into stomach area

Getty Images / imyskin

Ozempic vs. Metformin: How Are They Different?

Ozempic and metformin are approved to use along with improved diet and exercise to control type 2 diabetes. While Ozempic is only available for adults, metformin can be prescribed to children 10 and older.

Both Ozempic and metformin are proven to help lower blood sugar levels, which is something that can be measured by an A1c test. Studies have shown them to reduce blood sugar within two to three months.

Lowering A1c is crucial to improving diabetes outcomes and preventing complications from diabetes. Metformin and Ozempic have also been linked to potential weight loss among people with diabetes. This can benefit those with obesity or needing to lose weight to improve their diabetes and health outcomes.

Ozempic
  • Belongs to the GLP-1 receptor agonist drug class

  • Approved to treat type 2 diabetes in adults

  • Approved for weight loss to treat obesity under the brand-name Wegovy

  • No generic available

  • Taken by injecting it under the skin

  • Once-weekly dose

Metformin
  • Belongs to the biguanides drug class

  • Approved to treat type 2 diabetes in adults and children

  • Not approved for weight loss

  • Generic versions available

  • Taken by mouth in tablet form

  • Daily or twice daily dose

Although prices may vary, Ozempic is generally more expensive than metformin without insurance. It is a newer drug and doesn't yet have any available generic alternatives on the market.

Prescribers are aware of this and usually start with metformin to reduce the cost burden and increase adherence.  

A Word from Verywell

Metformin is taken daily and comes as a low-cost generic, while Ozempic is a weekly, more costly, brand-name injection that may not be available due to off-label prescribing. It is important to discuss convenience and cost with your healthcare provider.

Ozempic vs. Metformin: Which Is the Best Option?

Metformin has decades' worth of research on its effectiveness and safety. It is also generally a lower-cost option as generic versions are available. For these reasons, it is considered a mainstay of type 2 diabetes treatment and the preferred first-line therapy for lowering blood sugar.

This does not discredit the use of Ozempic. However, since it is a relatively new medication compared to metformin, further research is needed on the long-term benefits of its use.

Still, as newer medications hit the market, more options of first-line treatments are becoming available for different patient populations.

For example, Ozempic and other medications similar to it (e.g., dulaglutide or liraglutide) are now also considered first-line therapy options for people with heart disease or kidney problems, along with other conditions such as obesity. Other antidiabetic drugs are also available if metformin fails to successfully lower blood sugar or if side effects become intolerable.

Healthcare providers may also prescribe multiple antidiabetic drugs to be used together to achieve or sustain target diabetes goals.

Who Can Use Both Ozempic and Metformin?

People diagnosed with type 2 diabetes will either take metformin or another medication like Ozempic. These medications can be prescribed as monotherapy (taking just one) or can even be taken together to further improve their A1c if one therapy is not enough.

Unlike Ozempic, metformin can be taken by children 10 and older.

It is necessary to speak with your healthcare provider if you become pregnant or plan to become pregnant while on these drugs. Both metformin and Ozempic can be harmful to the fetus. Ozempic should be stopped at least two months before becoming pregnant.

How Do They Work?

Ozempic belongs to a class of medications called glucagon-like peptide 1 (GLP-1) receptor agonists that are responsible for reducing blood sugar levels in a complex and unique way.

As a GLP-1 receptor agonist, Ozempic works by helping the pancreas release insulin in response to high blood sugar levels in the body. This reduces the amount of sugar released into the bloodstream.

Ozempic can affect heart rate, lower blood pressure, and increase blood flow for healthier arteries or blood vessels. Ozempic is also known to contribute to weight loss due to the increase in the hormones that cause you to feel full and less hungry.

Metformin is a unique oral antidiabetic medication that works differently from other oral blood sugar–lowering drugs. Metformin is in a class of its own called biguanides. It helps decrease the liver's sugar production and the intestines' absorption of sugar while improving the body's sensitivity to making more insulin when needed.

Ozempic vs. Metformin: Dosage and Availability

Ozempic is a low-dose, once-weekly injection that is given subcutaneously usually under the skin of the abdomen, thigh, or upper arm. Metformin is commonly given as an oral tablet once or twice daily, depending on the prescribed dose.

Ozempic is relatively expensive and does not have a generic injection formulation available at a more affordable price. However, metformin is available in generic versions. It is inexpensive when sold as a generic compound instead of as a brand name product.

Common brand-name products for metformin are Fortamet and Glumetza (XR version).

Metformin may be more expensive when included as an ingredient with other oral diabetic medications. Formulations containing metformin include:

  • ActoPlus Met (metformin and pioglitazone)
  • Invokamet (metformin and canagliflozin)
  • Janumet (metformin and sitagliptin)
  • Synjardy (metformin and empagliflozin)
  • Xigduo XR (metformin XR and dapagliflozin)
  • Trijardy XR (metformin XR, empagliflozin, and linagliptin)

This list is most of the medications that contain metformin in them. Many of these agents also contain the XR metformin available for those who take higher doses, require fewer pills, or prefer XR formulations to reduce stomach-related side effects.

Side Effects and Safety Precautions

Ozempic and metformin share many side effects. The most common side effects that people may encounter while taking these two medications are:

  • Nausea or vomiting
  • Diarrhea
  • Stomach pain or discomfort
  • Indigestion or dyspepsia

Talk to your healthcare provider if you experience any severe or intolerable side effects, such as diarrhea, constipation, or other bothersome stomach and digestive issues.

Ozempic can cause serious side effects if not carefully monitored. Serious side effects include:

Metformin is a relatively safe medication but can cause serious complications if there are underlying issues or if you aren't getting enough nutrients in your diet.

Often, many people believe that eating healthier foods means only eating salads or vegetables and restricting their diet a lot more than before their diabetes diagnosis. However, this can lead to certain deficiencies in vitamins or minerals.

Long-term use of metformin can increase the risk of vitamin B12 deficiency. Therefore, eating a nutrient-rich diet and getting regular blood work done to monitor vitamin B12 levels is important while on metformin therapy. You can also talk to your provider about taking a multivitamin or supplement.

Ozempic vs. Metformin for Weight Loss

Ozempic has become a popular medication for weight loss and weight management. The FDA has approved semaglutide, Ozempic's active ingredient, under the brand name Wegovy for weight loss in people with obesity.

Metformin has been associated with mild to moderate weight loss, but it is not approved for this purpose. Metformin is also known to cause stomach-related side effects, such as diarrhea, which can affect appetite and food intake.

Let your healthcare provider know if you experience severe nausea, diarrhea, or stomach pain while on metformin.

Summary

Ozempic and metformin are both effective medications used to lower blood sugar levels in people with type 2 diabetes. While metformin has traditionally been a first-line treatment choice, Ozempic has increasingly become more common for other patient populations, such as people with obesity.

After making a diagnosis of diabetes, your healthcare provider may prescribe metformin as the first choice to achieve your blood sugar targets. Over time, you may need additional antidiabetic agents, such as Ozempic.

Other factors, such as cost, side effects, and other health conditions, can inform which treatment is best suited for your individual needs.

The author would like to recognize and thank Jaycob Mathew Peña for contributing to this article.

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