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Does Metformin Cause Hair Loss?

Knox Beasley, MD

Reviewed by Knox Beasley, MD

Written by Geoffrey C. Whittaker

Published 03/19/2021

Updated 04/04/2024

Metformin is a drug used to treat type 2 diabetes mellitus. While some may notice fallout or thinning when taking this medication, the connection might not be what you think. So, does metformin cause hair loss? We have answers.

Metformin isn’t known to cause hair loss. However, hair loss is correlated with type 2 diabetes. So, technically, you could take metformin for hair loss related to diabetes or even be prescribed metformin for hair growth in very specific circumstances.

But can metformin cause hair loss, and if so, how? We’ll cover this below, along with strategies for maintaining a full head of hair.

Metformin is a prescription medication used to treat high blood sugar in those with type 2 diabetes who are resistant to the effects of insulin. It’s in a class of drugs known as biguanides.

This medication works by decreasing the amount of glucose your body absorbs from food and the amount of glucose made in your liver while reducing blood glucose overall.

It can also increase your body’s sensitivity to insulin, which controls blood sugar levels.

Side note: Metformin isn’t used to treat type 1 diabetes.

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While hair loss may not be a side effect of metformin, it can be associated with diabetes. So, if you’re taking metformin for diabetes and experiencing hair loss, it may have less to do with your medication and more to do with your health condition.

Diabetes is a serious health condition in which the body struggles to moderate glucose levels and develops insulin resistance. Left untreated, it can lead to even more severe problems up to and including death.

Managing diabetes through lifestyle approaches and medication (like metformin) can decrease those risks.

In fact, one of the most likely explanations for why you might see hair loss with this chronic health condition is that the symptoms of diabetes can, over time, cause you to experience hair loss.

Diabetes and Hair Loss

It’s hard to pinpoint what comes first — hair loss, diabetes or other associated health conditions. In any case, the scientific literature shows that they’re all correlated.

A small study of 100 men in India found that androgenetic alopecia (male pattern baldness) can be an early warning sign of metabolic syndrome. This condition is a collection of symptoms pointing to heart and diabetes-related problems.

A larger study with over 7,000 subjects also concluded that androgenetic alopecia could be a predictor of diabetes and heart disease. Researchers noted that participants with moderate to severe male pattern hair loss had a “significantly higher” risk of death from diabetes.

Also, hair loss on the legs can indicate peripheral artery disease (when narrow blood vessels prevent blood flow to the limbs) among people with type 2 diabetes.

Learn more about diabetes and hair loss in our blog.

Metformin itself isn’t thought to cause hair loss, but type 2 diabetes and PCOS (polycystic ovary syndrome) — the conditions it’s prescribed to treat — can cause hair loss. Studies also show that metformin can contribute to vitamin B12 deficiency. Since this nutrient is essential for healthy hair growth, a deficiency may lead to hair loss.

In fact, vitamin deficiency is known to be one of the reasons you might see hair fallout. Here’s what we know about low vitamin B12 levels and thinning hair.

Metformin and Vitamin B12

Vitamin B12 deficiency is associated with a number of problems, including weakness, weight loss, constipation and — yes — hair loss.

But before you say “case closed,” it’s important to understand that B12 deficiency is really, really rare.

You simply don’t need much vitamin B12. Plus, it’s fairly easy to get either through supplements or as part of your daily intake of foods like fish, eggs, meat and milk.

However, as noted, metformin may increase your risk of vitamin b12 deficiency. This could contribute to hair thinning or interrupt your hair’s natural growth cycle.

Other Potential Causes of Hair Loss

While some medications might make you shed more than usual, there are other potential causes of hair loss to consider.

For instance, male pattern baldness (the most common type of hair loss among men) is often caused by genetic factors.

Besides diabetes, various illnesses can also contribute to thinning and fallout.

This includes:

  • Nutritional deficiencies

  • Hormonal imbalances

  • Fungal infection

  • Hyperglycemia

  • Trichotillomania (compulsive hair-pulling)

  • Cancer

  • Alopecia areata, an autoimmune disease

  • Other autoimmune disorders

Learn more about the health conditions that can cause hair loss in our blog.

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As with almost any prescription drug, metformin comes with risks and side effects. However, nowhere in the official documentation of metformin does it indicate hair loss as a potential risk.

According to the FDA (U.S. Food and Drug Administration), the most common adverse reactions of metformin include:

  • Diarrhea

  • Nausea

  • Gas

  • Indigestion

  • Stomach discomfort

  • Headache

  • Weakness

One of the most serious (but quite rare) risks of metformin is lactic acidosis, the buildup of lactic acid.

Lactic acidosis can be fatal, and the early signs are sometimes easy to miss. Abdominal pain, a general sense of not feeling well and breathing difficulties could be indicators.

A Side Note on Metformin Safety Recalls

Many manufacturers of metformin hydrochloride have recalled their medications because of potentially high levels of an ingredient found to cause cancer.

This ingredient, nitrosodimethylamine (NDMA), may be present in some metformin extended-release formulas above the acceptable limit. But as of early 2021, at least 13 drug companies have recalled their extended-release formulas.

In many cases, androgenic alopecia can be treated. With guidance from a healthcare provider, hair loss treatments may include medication, lifestyle changes and managing related health conditions.

Hair Loss Medication

The two most common and promising treatments are topical minoxidil and oral finasteride.

Minoxidil is applied to the scalp, where it stimulates hair growth. Finasteride blocks the conversion of testosterone to DHT (short for dihydrotestosterone), a hormone known to trigger hair loss.

Managing Related Health Conditions

If you have diabetes, you’ll want to consult a healthcare professional to discuss treatment for diabetes and get medical advice on lifestyle changes (including what foods to eat) that can help you manage high blood sugar levels.

A medical professional or dermatology expert can help you rule out other potential causes of hair loss, like androgen hormonal imbalance (androgenic alopecia) or immune system issues (alopecia areata).

Your provider may run tests to check for anemia and insulin resistance while assessing your thyroid and other critical functions.

Hair loss treatments, delivered

Here’s what to keep in mind about metformin and hair loss:

  • There are currently no scientific indications that metformin causes hair loss.

  • However, we know the disease metformin treats — type 2 diabetes — is associated with hair loss.

  • In fact, loss of hair follicles may be an early warning sign of type 2 diabetes and other health problems.

  • Fortunately, there are some viable solutions to potentially slow down or stop the hair loss you might be experiencing.

  • But don’t discontinue the use of metformin without speaking to your healthcare provider.

Talking with a healthcare provider about your condition and which treatment option(s) might be right for you is a good first step.

Hims has finasteride medication, as well as minoxidil foam and minoxidil liquid solution. We also carry a combination topical treatment, a two-in-one finasteride & minoxidil spray.

Additionally, we have biotin gummies for hair growth, DHT-blocking saw palmetto shampoo, volumizing shampoo and conditioner.

You can also get an online prescription for metformin for weight loss, following a consultation with a licensed healthcare provider. Explore your options today.

8 Sources

Hims & Hers has strict sourcing guidelines to ensure our content is accurate and current. We rely on peer-reviewed studies, academic research institutions, and medical associations. We strive to use primary sources and refrain from using tertiary references.

  1. Chin, E., (2013, May) Androgenetic alopecia (male pattern hair loss) in the United States: What treatments should primary care providers recommend? Journal of the American Association of Nurse Practitioners. 25(8): 395-401. Retrieved from
  2. Miranda, J. et. al. (2016, Aug.) Hair follicle characteristics as an early marker of type 2 diabetes. Medical Hypotheses. 95: 39-44. Retrieved from
  3. U.S. National Institutes of Health. (2020, Mar.) Metformin. MedlinePlus. Retrieved from
  4. Kumar, K., et. al. (2018, Mar.) Association of androgenetic alopecia with metabolic syndrome: A case-control study on 100 patients in a tertiary care hospital in South India. Indian Journal of Endocrinology and Metabolism. 22(2): 196-199. Retrieved from
  5. Kotsalidis, N., Lucier, R. (2021, Jan.) companies recall extended release metformin due to cancer causing substance. Retrieved from
  6. U.S. Food and Drug Administration. (2017, Apr.) Glucophage (metformin hydrochloride) Tablets. Retrieved from,021202s021s023lbl.pdf
  7. Su, L., et. al. (2013, May) Association of androgenetic alopecia with mortality from diabetes mellitus and heart disease. JAMA Dermatology. 149(5): 601-606. Retrieved from
  8. Bakry, O. A., Shoeib, M. A., El Shafiee, M. K., & Hassan, A. (2014). Androgenetic alopecia, metabolic syndrome, and insulin resistance: Is there any association? A case-control study. Indian dermatology online journal, 5(3), 276–281.
Editorial Standards

Hims & Hers has strict sourcing guidelines to ensure our content is accurate and current. We rely on peer-reviewed studies, academic research institutions, and medical associations. We strive to use primary sources and refrain from using tertiary references. See a mistake? Let us know at [email protected]!

This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.

Knox Beasley, MD

Dr. Knox Beasley is a board certified dermatologist specializing in hair loss. He completed his undergraduate studies at the United States Military Academy at West Point, NY, and subsequently attended medical school at Tulane University School of Medicine in New Orleans, LA. 

Dr. Beasley first began doing telemedicine during his dermatology residency in 2013 with the military, helping to diagnose dermatologic conditions in soldiers all over the world. 

Dr. Beasley is board certified by the American Board of Dermatology, and is a Fellow of the American Academy of Dermatology.

Originally from Nashville, TN, Dr. Beasley currently lives in North Carolina and enjoys spending time outdoors (with sunscreen of course) with his wife and two children in his spare time. 





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