8 Potential side effects to know before taking biotin supplements

Vitamin H, commonly known as biotin, is a member of the vitamin B complex that helps convert carbohydrates and lipids into fuel. Healthy individuals produce normal amounts of biotin in the body through the gut’s microorganisms and by sourcing this vitamin from food. 

Some benefits of biotin include having healthy hair and nails, increased hair growth for biotin-deficient, healthy skin, and protection against cardiovascular diseases and type 2 diabetes mellitus. 

Understanding the potential side effects of biotin supplements is essential before incorporating them into your wellness routine. While biotin offers numerous health benefits, it’s crucial to be aware of any potential drawbacks to make informed decisions about its use.

What are the side effects of taking biotin supplements?

Vitamin H, commonly known as biotin, is a member of the vitamin B complex that helps convert carbohydrates and lipids into fuel. Healthy individuals produce normal amounts of biotin in the body through the gut’s microorganisms and by sourcing this vitamin from food. 

Some benefits of biotin include healthy hair and nails, increased hair growth for biotin-deficient people, healthy skin, and protection against cardiovascular diseases and type 2 diabetes mellitus. 

Food sources of biotin include beef, egg yolks, pork, milk, white mushrooms, cheese, lettuce, carrots, apples, spinach and oats. 

The functions of B vitamins include the following: 

  • Proper functioning of the nervous system and the brain 
  • Promote healthy skin, eyes, hair and liver
  • Normal growth of the fetus during the mother’s pregnancy 

Biotin is a water-soluble vitamin, and any excess biotin in food is excreted through the urine. Hence, it is rare to have biotin toxicity due to excessive consumption of food sources rich in biotin. 

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Adequate intake (AI) for biotin is 30 micrograms per day. People with biotin deficiency include those with inherited genetic disorders that prevent them from using biotin correctly or from producing this vitamin in the body. 

Some biotin-deficient people also have medical conditions that prevent the adequate uptake of biotin in the body. For example, people with Chron’s disease struggle to absorb nutrients from the small intestine [1]. 

Individuals with biotin deficiency due to medical conditions or genetic factors can receive biotin supplementation to address the shortage. 

However, for some, taking biotin supplementation results in side effects. Here are eight potential side effects to be aware of when you are taking biotin supplements: 

1. Digestive issues

Experiencing digestive discomfort while taking biotin supplements is not uncommon. Here’s a quick overview to help you understand and manage it:

  • Upset stomach: Biotin can sometimes cause nausea, cramping, or diarrhea, especially in high doses.
  • Gastric distress: Some individuals may experience bloating or gas after taking biotin.
  • Timing matters: Taking biotin with food or dividing doses throughout the day can help reduce digestive upset.

Managing digestive discomfort:

  • Drink plenty of water to help ease digestion.
  • Begin with a lower dose and gradually increase to allow your body to adjust.
  • If symptoms persist, consult your healthcare provider for personalized advice.

2. Acne breakouts

Experiencing unexpected breakouts while taking biotin supplements is something many people face. Here’s a rundown on why it happens and what you can do about it:

  • Increased sebum production: Biotin can boost oil production in your skin, leading to clogged pores and acne flare-ups [2].
  • Hair growth stimulation: While biotin promotes hair growth, it can also affect the skin’s oil glands, contributing to acne formation.
  • Location matters: Breakouts often appear on the face, especially around the chin and jawline, but they can also appear on the back and chest.

Managing acne with biotin:

  • Keep your skin clean by washing it regularly with a gentle cleanser.
  • Hydrating your skin can help balance oil production.
  • If acne persists, seek advice from a skincare professional for personalized recommendations.

3. Insomnia 

Insomnia, or the inability to sleep, is a common disorder that can lead to serious illness when left untreated. There are reports that excessive biotin supplementation can lead to insomnia. 

Since biotin supplements are needed to metabolize fats and carbohydrates and turn them into energy, excessive biotin intake at nighttime might lead to a surge of energy. 

This surge of energy may make it difficult for you to sleep. Hence, taking biotin early in the morning might help prevent insomnia or trouble sleeping. 

4. Interference with laboratory tests 

When taking biotin supplements, knowing how they can affect your lab results is important. Here’s what you need to know:

  • Inaccurate readings: Biotin can interfere with certain lab tests, such as those for thyroid function and hormone levels, leading to false results.
  • Potential risks: Misinterpreted lab results could lead to incorrect treatments or diagnoses.
  • Communication is key: Inform your healthcare provider if you take biotin supplements, especially before undergoing lab tests.

Navigating lab tests with biotin:

  • Stop taking biotin supplements at least 24 to 48 hours before scheduled lab tests to minimize interference [3].
  • If you’re unsure when to stop taking biotin or how it may affect your tests, consult your healthcare provider for guidance.

5. Allergic reactions

Being allergic to biotin supplements is rare, but it’s essential to be aware of the signs if you experience them. Here’s what to look out for:

  • Skin rash or hives: These may appear suddenly after taking biotin, indicating an allergic reaction.
  • Itching or swelling: If you notice itching, swelling, or redness, especially around your face or throat, it could be a sign of allergy.
  • Breathing difficulties: In severe cases, allergic reactions can cause difficulty breathing or throat tightening, which requires immediate medical attention.

Managing allergic reactions:

  • If you suspect an allergic reaction, stop taking biotin immediately and seek medical advice.
  • If you have a history of allergies, consult an allergist before starting biotin supplementation to assess your risk.

6. Drug interactions

Like other B vitamins, biotin can interact with other medications you might be taking. Hence, it is essential to talk to your doctor if you are currently taking drugs that have broken down and changed the liver. For instance, biotin may interfere with the breakdown of certain medications in the liver. 

Biotin might increase or decrease the breakdown of these drugs. Hence, taking biotin might significantly increase the side effects of certain medicines if it increases the drug’s level in the liver [4]. 

Here are some examples of drugs that are changed by the liver and might be affected by the intake of biotin: 

  • Haloperidol (treatment of psychotic disorders) 
  • Fluvoxamine (treatment of depression) 
  • Clozapine (an antipsychotic medication) 
  • Cyclobenzaprine (muscle relaxer) 
  • Imipramine (antidepressant) 
  • Olanzapine (treatment for schizophrenia) 

7. Kidney problems 

Be mindful of the potential impact biotin supplements can have on your kidneys. Here’s what you should know:

Biotin is primarily excreted through the kidneys, so taking high doses over a long period could strain your kidneys.

Individuals with pre-existing kidney conditions may be more susceptible to experiencing kidney problems while taking biotin.

If you have kidney issues or are at risk, monitoring your kidney function regularly is crucial, especially if you’re considering biotin supplementation.

By staying informed and discussing any concerns with your healthcare provider, you can decide whether biotin supplementation suits you. 

8. Risk of overdose

Taking excessive amounts of biotin supplements can pose risks to your health. Here’s what you need to know:

  • While biotin is water-soluble and generally considered safe, consuming high doses can lead to toxicity symptoms such as nausea, vomiting, and skin rashes.
  • Overdosing on biotin may also exacerbate drug interactions and interfere with the absorption of other vitamins and minerals [5].
  • Always follow recommended dosage guidelines and consult your healthcare provider before increasing your biotin intake, especially if you already take other supplements or medications.
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Final takeaways

Biotin supplements are relatively safe and tolerable, even in very high doses. Since biotin is a water-soluble vitamin, any excess is excreted via the kidneys and urine.

However, in cases where individuals have medical conditions that prevent optimal uptake of biotin, it can lead to excess biotin in the bloodstream. 

When biotin is not appropriately used in the body or is present in excessively high amounts, this can lead to side effects such as insomnia or trouble sleeping, acne, digestive upset, skin rashes, interference with laboratory test results, excessive thirst and kidney problems.

Reducing high-dose biotin supplementation often resolves most of these side effects. However, some side effects can only be addressed by completely removing biotin supplements. 

Considering the potential side effects when taking biotin supplementation, it is always best to consult your doctor to ensure you take this vitamin safely. Taking the appropriate dose at the right time would prevent drug-to-drug interactions. 

Finally, biotin is an essential vitamin that ensures good metabolism of carbohydrates and fats. The potential side effects of this vitamin can be addressed by taking the appropriate dosage or removing biotin supplementation.

Concerns about the latter can be addressed by obtaining biotin from food. There are still no studies suggesting a potential overdose of the vitamin when this is sourced from biotin-rich foods.


Can I take biotin with other vitamins?

Yes, biotin is generally safe to take alongside other vitamins. However, it’s advisable to consult your healthcare provider to ensure there are no potential interactions with specific supplements or medications.

How long does it take to see results from biotin supplementation?

Results vary depending on individual factors like dosage and hair growth cycle, but many people start noticing improvements in hair and nail health within a few weeks to a few months of consistent use.

Are there any side effects of taking biotin?

Some potential side effects of biotin supplementation include acne breakouts, digestive issues, and allergic reactions, although these are relatively rare.

Can biotin interfere with laboratory tests?

Yes, biotin can interfere with certain lab tests, such as thyroid function tests and hormone assays, potentially leading to inaccurate results.

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Photograph: Lelia_Milaya/Envato