RECALL OF METFORMIN EXTENDED RELEASE

In May 2020, the Food and Drug Administration (FDA)Trusted Source recommended that some makers of metformin extended release remove some of their tablets from the U.S. market. This is because an unacceptable level of a probable carcinogen (cancer-causing agent) was found in some extended-release metformin tablets. If you currently take this drug, call your healthcare provider. They will advise whether you should continue to take your medication or if you need a new prescription.

Metformin can help treat type 2 diabetes and polycystic ovary syndrome, but some people worry that it may cause hair loss. However, little evidence supports the claim that metformin can cause hair loss.

Doctors typically prescribe metformin as a first-line treatment for people with type 2 diabetes. Alongside diet and exercise, metformin can help a person control their insulin and blood sugar levels.

Doctors sometimes also prescribe metformin for people with polycystic ovary syndrome (PCOS). Raised insulin and blood sugar levels are common symptoms of PCOS, and metformin can help reduce them.

In this article, we explore the possible relationship between metformin and hair loss, as well as relevant research. We also describe some of the treatment options for reducing the impact of hair loss if it does occur.

A note about sex and gender

Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Learn more.

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On rare occasions, people have reported a link between metformin and thinning hair or hair loss. However, it is unclear whether metformin is directly responsible for this issue or if other factors play a role.

For example, an older 2017 case reportTrusted Source in Current Drug Safety described how a 69-year-old man with type 2 diabetes suddenly lost his eyebrows and eyelashes.

The man took a combination of metformin, and another diabetes medication called sitagliptin (Januvia).

Doctors used clinical tests to rule out any systemic or skin diseases that might be contributing to hair loss. The authors of the report concluded that there was a possible association between the medication and hair loss.

However, as this case study involved just one person, it is difficult to move from these findings to a general trend suggesting a significant relationship between metformin and hair loss.

Metformin might reduce the risk of hair loss in people who take it to treat PCOS, according to an older randomized clinical trial from 2016Trusted Source. As hair loss can be a symptom of PCOS, treating the condition can reduce its effects.

Additionally, a 2021 in vitro study also found that metformin may promote hair follicle regeneration. However, further research is needed and findings from in vitro studies are not always replicable in humans.

Another possibility is that metformin may indirectly contribute to hair loss in people with diabetes.

Older research from 2016Trusted Source suggests that taking metformin long-term can cause B12 deficiency and anemia. Hair loss is a potential symptom of both of these conditions.

According to Dr. Jill Crandall, Professor of Medicine at Albert Einstein College of Medicine in New York, metformin might reduce the gut’s abilityTrusted Source to absorb vitamin B12. This reduced absorption may explain why people experience symptoms of B12 deficiency.

In addition to hair loss, other vitamin B12 deficiency symptoms include:

Mild deficiencies may not cause any symptoms.

A doctor may advise that people who are taking metformin should increase their intake of B12-rich foods or take B12 supplements to treat or prevent this deficiency.

Alternatively, they may recommend getting shots of B-12 that bypass the gut and enter the bloodstream directly.

Other potential causes of hair loss may relate to a person’s medical condition rather than the use of metformin to treat it.

These include the following health problems.

High blood sugar

A buildup of sugar in the blood can damage blood vessels and organs throughout the body. Healthy blood vessels are necessary for transporting oxygen and nutrients to each part of the body, including the hair follicles.

If the hair follicles do not receive enough oxygen and nutrients, this can affect the growth of hairs. More hair may fall out, or new hair may grow at a slower rate than usual.

Type 1 diabetes is also associated with the development of alopecia areata, according to research in an older 2016 study. In people with this condition, the immune system mistakenly attacks the hair follicles, causing hair to fall out in patches.

People with type 2 diabetes often have insulin resistance, which means that the cells in their body do not respond to insulin appropriately. One older 2014 studyTrusted Source reports a link between insulin resistance and a type of alopecia, or hair loss.

PCOS

Females with PCOS have abnormally high levels of androgens, which are hormones that are typically higher in males. Occasionally, this hormonal imbalance can cause a type of hair loss. It may also cause excess facial hair and acne.

People with PCOS and obesity might also have insulin resistance, which may be linked to hair loss.

Stress

Stress may cause a rise in hormone levels that leads to an increase in blood sugar levels. This may contribute to insulin resistance and diabetes development. Additionally, diabetes may cause irregularities in the regulation of stress hormones.

People who experience stress may also be less likely to follow their diabetes care plan, which may lead to worsening symptoms.

PCOS can also cause emotional stress, which can further affect hormone levels in the body. These hormonal changes may cause or contribute to thinning hair.

Metformin may cause several side effects. It is best to speak to a doctor about any side effects that last for more than a few days.

Anyone who experiences severe side effects when taking metformin should seek immediate medical attention.

Common side effects

The most common side effects of metformin are:

Less common side effects

Less often, people taking metformin may experience:

Rare side effects

In rare cases, metformin may cause anemia. The symptoms of anemia can include:

Severe side effects

In severe cases, metformin may cause lactic acidosis.

Lactic acidosis is a dangerous complication that causes a buildup of lactic acid in the body. This can lead to diabetic coma and might even be fatal for some people with extremely high levels of lactic acid.

It is vital to contact emergency services immediately if any of these reactions occur when taking metformin.

People may be able to reverse or slow down hair loss using medications, surgery, and home remedies. However, this is not always possible.

Sometimes, a person may need a combination of treatments, such as those below.

Medications

Some drugs can treat hair loss. These include minoxidil (Rogaine), which is an over-the-counter (OTC) medication. The treatment takes at least 4 months to work, and a person usually applies it to their scalp twice daily.

Finasteride (Propecia) is a prescription medication for males who experience hair loss. It is available in pill form, and a person needs to take it on an ongoing basis to see significant results.

Some females with PCOS may experience relief from hair loss if they take birth control pills.

If a particular medication causes hair loss, a doctor may recommend an alternative treatment. It is essential to consult a doctor before stopping any prescription drug.

Hair transplant surgery

People with permanent hair loss may wish to consider a hair transplant.

During this procedure, a surgeon or dermatologist will remove tiny sections of skin from other parts of the individual’s head or body. They will then implant the hair follicles from this skin onto the areas.

A person may require multiple sessions to achieve satisfactory results. Hair transplantation is often an expensive option.

Home remedies

People may be able to reverse or prevent further hair loss by doing the following:

  • managing stress
  • asking a doctor to check for nutrient deficiencies
  • avoiding damaging hair treatments, such as tight hairstyles and heat styling
  • treating underlying conditions, like diabetes and PCOS

Individuals who notice sudden or excessive hair loss should seek consultation with a doctor.

This symptom may indicate an underlying medical condition, or it may be a side effect of an OTC or prescription medication.

The doctor will recommend treatments, lifestyle adjustments, and natural remedies that may help prevent or reverse a person’s hair loss.

What are the other side effects of metformin?

Some common side effects include bloating, flatulence, diarrhea, weakness or fatigue, and a metallic taste.

These often become less bothersome as the body adjusts to the metformin dose but can be unpleasant to deal with. If these, or other side effects described above, persist, or become worse, a person should contact their doctor.

Will hair grow back after taking metformin?

People may be able to reverse or slow down hair loss using medications, hair transplant surgery, and lifestyle changes. However, this is not always possible.

Does hair grow back after falling out from roots?

Yes, hair can grow back after falling out from the roots. Although, root damageTrusted Source may cause increased hair loss.

Doctors prescribe metformin to treat high levels of blood sugar and insulin in people with type 2 diabetes or PCOS.

In rare cases, there may be a link between hair loss and taking metformin. It is also possible that metformin may cause hair loss indirectly. Taking metformin long-term may increase the risk of vitamin B12 deficiency, which can sometimes cause hair loss.

However, it is also possible that hair loss in people taking metformin is a result of a health condition rather than the medication.

Treatments for hair loss include medications, hair transplant surgery, and home remedies.