Biotin – StatPearls – NCBI Bookshelf

Karlyle G. Bistas; Prasanna Tadi.

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Last Update: May 23, 2023.

Continuing Education Activity

Biotin is an alternative medication used in the management and treatment of pathological hair conditions. It is in the vitamin class of drugs. This activity reviews the indications, action, and contraindications for biotin as a valuable agent in the therapy of biotin deficiency and hair conditions. In addition, this activity will highlight the mechanism of action, adverse event profile, and other key factors (e.g., off-label uses, dosing, pharmacodynamics, pharmacokinetics, monitoring, relevant interactions) pertinent for members of the healthcare team in the management of patients with brittle hair and related conditions.

Objectives:

• Review the treatment considerations for patients with brittle hair and nails.

• Explain the indications for biotin use.

• Outline the typical presentation of a patient with biotin deficiency.

• Summarize the importance of collaboration and communication amongst the interprofessional team to enhance the delivery of care for patients affected by pathological hair conditions and patients receiving biotin.

Access free multiple choice questions on this topic.

Indications

Biotin (B7 or vitamin H) is a water-soluble vitamin, which has received publicity for promoting the growth of hair and nails. There are limited studies, which confirm the exact indications of biotin.[1] Biotinidase deficiency is uncommon but has been documented. Frank deficiency of biotinidase may present as conjunctivitis, ataxia, seizure, skin infections, and developmental delay in children.[2] Biotin may have benefits in those suffering from pathologic brittle hair syndrome or uncombable hair syndrome.[3][4] Otherwise, indications for supplementation remain unnecessary in healthy individuals. [1] Biotin deficiencies would require inborn errors of metabolism. Documentation on supplementation in healthy individuals remains unclear. To date, there have been no trials supporting claims of biotin supplementation being used to improve hair quality or quantity, or nail growth.[5] The U.S. Food and Drug Administration does not recommend daily biotin usage, although breastfeeding or pregnant patients are recommended to take from 5 mcg/ to 35 mcg/day. Pregnancy and smoking increase the metabolism of biotin and would require increased intake, although controversial.[6][7] There is limited evidence to suggest biotin can provide a benefit to hair and nail growth.

Mechanism of Action

Biotin also acts as a coenzyme for multiple carboxylases in humans, and it changes the irreversible carboxylation of acetyl-CoA to malonyl-CoA.[2] These enzymes are vital in numerous metabolic processes. Recently, the new roles of biotin have been acknowledged, in particular, the roles in cell signaling and epigenetic regulation. [8] Biotin’s mechanism of action occurs by attaching to specific lysine residues.[9] The side effects of ingesting too much biotin could include an upset stomach, although it remains a vitamin with very low side effects. Biotin uptake by human colonic epithelial is a carrier-mediated process.[10] Vitamin B7 is a cofactor for three significant carboxylation reactions, which include the conversion of pyruvate to oxalacetate, acetyl-CoA to malonyl-CoA, and propionyl-CoA to methylmalonyl-CoA. A carboxylase reaction includes the transfer of carbon with the assistance of biotin. Essentially these conversions assisted by biotin break down food into glucose, the primary carbohydrate source for the brain and body.

Administration

Biotin appears to be widely protein-bound.[4] Recommendations for biotin intake range from 5 ug to 35 ug per day, depending on circumstances. For example, there is no daily recommendation, but biotin use may be appropriate and warranted for a breastfeeding mother due to increased demand for nutrients. Biotin is also required for the normal development of the fetus when the mother is pregnant. When needed, the most common route of administration for biotin is orally, but biotin administration can also be in an IV form. Therefore, there is no indication for daily use by the U.S. Food and Drug Administration, but when indicated, its administration is usually via the oral route. The IV form is for cases where biotin deficiency is apparent and symptomatic. It can also be useful when treating trichothiodystrophy (TDD), a rare autosomal recessive disorder, which appears to benefit from biotin intake. The tablet form of biotin usually comes in the forms of 10, 50, or 100 mcg. It is metabolized by the liver and excreted by the kidneys.

Adverse Effects

Biotin consumption for beneficial means remains unclear, but it has been considered a very difficult drug to overdose on or cause injury to the body. When taking anticonvulsants such as carbamazepine or phenobarbital, the requirements for biotin increase due to these medications inhibiting uptake into the brush borders of membrane vesicles. [4] Smoking also metabolizes biotin quickly; therefore, increased doses may be warranted when indicated if the patient is a smoker. Information on other drug interactions is minimal. There have been no reported injuries for taking too much biotin, but there are documented cases of biotin deficiency. 

Biotin can interfere with some hormone assays. In immunoassays using the streptavidin-biotin interaction, the interference may induce both false-positive and false-negative results. The hormone levels affected may include thyroid functions, gonadotrophins, and vitamin D.[11][12]

Contraindications

Research supporting claims for the use of biotin for nails and hair remains ambiguous, but there has been well-documented research on the interactions of biotin and other drugs. There are no evident contraindications to taking this vitamin. Biotin is a safe and nontoxic vitamin that the body excretes when in excess. There are no known herbal interactions with biotin. Although not a contraindication, it is important to note that if a person is taking biotin and smoking, they may require increased doses due to increased biotin metabolism.

Monitoring

Dermatologic manifestations appear to be the first sign of biotin deficiency. Biotin plasma concentration levels range from 400 to 1200 ng/L.[1] The daily recommendation for biotin if and when indicated has undergone research, although there appears to be no specific therapeutic index. In circumstances where biotin deficiency is a concern, the urinary biotin concentrations are testable. Although rare, if deficient, a patient may present with dermatitis, enteritis, or alopecia. Antibiotic use or extreme, excessive intake of raw egg whites may induce a state of deficiency, which is very rare.

Toxicity

There is no specific antidote for overdosing on biotin. Excess in the body is rare, and since biotin is a water-soluble vitamin, it is excreted in the urine when in excess. Signs and symptoms of biotin overdose may include and are not limited to insomnia, excessive thirst, and urination. Since biotin has documentation in playing a role in postprandial glucose control, it bears mention that excess would cause signs and symptoms of a person experiencing hyperglycemia (e. g., increased thirst).[13] Diabetic patients should, therefore, be cautious before taking biotin. Although not impossible, it would be very difficult to overdose on biotin. Anaphylaxis is always a common concern with any medication but would present with systemic signs and symptoms. In rare cases, eosinophilic pleuropericardial effusion, a life-threatening condition, may occur.[14] Poison control centers should always be contacted with a suspected overdose.

Enhancing Healthcare Team Outcomes

Clinicians, nurses, physician assistants, and pharmacists must educate patients when confronted with the matter that regular biotin use is not indicated and also not well-documented. Interprofessional team members should be aware that biotin marketing often claims it is “a magic pill for hair and nails,” but the benefits remain unclear. Without the research to support regular usage, heavily marketed claims by the beauty and supplementation industry need to be challenged to examine the efficacy and safety of this drug, which they advertise for regular use. With the epidemic of type 2 diabetes in the United States, further exploration regarding biotin’s role in glucose control requires investigation since studies have concluded it may be beneficial for obese patients and those with type 2 diabetes.[13]

Review Questions

• Access free multiple choice questions on this topic.

• Comment on this article.

References

1.

Patel DP, Swink SM, Castelo-Soccio L. A Review of the Use of Biotin for Hair Loss. Skin Appendage Disord. 2017 Aug;3(3):166-169. [PMC free article: PMC5582478] [PubMed: 28879195]

2.

Zempleni J, Wijeratne SS, Hassan YI. Biotin. Biofactors. 2009 Jan-Feb;35(1):36-46. [PMC free article: PMC4757853] [PubMed: 19319844]

3.

Al-Eitan LN, Alqa’qa’ K, Amayreh W, Khasawneh R, Aljamal H, Al-Abed M, Haddad Y, Rawashdeh T, Jaradat Z, Haddad H. Identification and Characterization of BTD Gene Mutations in Jordanian Children with Biotinidase Deficiency. J Pers Med. 2020 Jan 21;10(1) [PMC free article: PMC7151559] [PubMed: 31973013]

4.

Zempleni J, Mock DM. Biotin biochemistry and human requirements. J Nutr Biochem. 1999 Mar;10(3):128-38. [PubMed: 15539280]

5.

Soleymani T, Lo Sicco K, Shapiro J. The Infatuation With Biotin Supplementation: Is There Truth Behind Its Rising Popularity? A Comparative Analysis of Clinical Efficacy versus Social Popularity. J Drugs Dermatol. 2017 May 01;16(5):496-500. [PubMed: 28628687]

6.

Sealey WM, Teague AM, Stratton SL, Mock DM. Smoking accelerates biotin catabolism in women. Am J Clin Nutr. 2004 Oct;80(4):932-5. [PMC free article: PMC1450014] [PubMed: 15447901]

7.

Zempleni J, Mock DM. Bioavailability of biotin given orally to humans in pharmacologic doses. Am J Clin Nutr. 1999 Mar;69(3):504-8. [PubMed: 10075337]

8.

Zempleni J. Uptake, localization, and noncarboxylase roles of biotin. Annu Rev Nutr. 2005;25:175-96. [PubMed: 16011464]

9.

Lamhonwah AM, Quan F, Gravel RA. Sequence homology around the biotin-binding site of human propionyl-CoA carboxylase and pyruvate carboxylase. Arch Biochem Biophys. 1987 May 01;254(2):631-6. [PubMed: 3555348]

10.

Said HM, Ortiz A, McCloud E, Dyer D, Moyer MP, Rubin S. Biotin uptake by human colonic epithelial NCM460 cells: a carrier-mediated process shared with pantothenic acid. Am J Physiol. 1998 Nov;275(5):C1365-71. [PubMed: 9814986]

11.

Piketty ML, Polak M, Flechtner I, Gonzales-Briceño L, Souberbielle JC. False biochemical diagnosis of hyperthyroidism in streptavidin-biotin-based immunoassays: the problem of biotin intake and related interferences. Clin Chem Lab Med. 2017 May 01;55(6):780-788. [PubMed: 27732554]

12.

Samarasinghe S, Meah F, Singh V, Basit A, Emanuele N, Emanuele MA, Mazhari A, Holmes EW. BIOTIN INTERFERENCE WITH ROUTINE CLINICAL IMMUNOASSAYS: UNDERSTAND THE CAUSES AND MITIGATE THE RISKS. Endocr Pract. 2017 Aug;23(8):989-998. [PubMed: 28534685]

13.

Xiang X, Liu Y, Zhang X, Zhang W, Wang Z. [Effects of biotin on blood glucose regulation in type 2 diabetes rat model]. Wei Sheng Yan Jiu. 2015 Mar;44(2):185-9, 195. [PubMed: 25997216]

14.

Debourdeau PM, Djezzar S, Estival JL, Zammit CM, Richard RC, Castot AC. Life-threatening eosinophilic pleuropericardial effusion related to vitamins B5 and H. Ann Pharmacother. 2001 Apr;35(4):424-6. [PubMed: 11302404]

Disclosure: Karlyle Bistas declares no relevant financial relationships with ineligible companies.

Disclosure: Prasanna Tadi declares no relevant financial relationships with ineligible companies.

Biotin Side Effects: How Safe Is This Supplement?

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By Jillian Levy, CHHC

September 19, 2022

Biotin, also called vitamin B7, is a nutrient that’s often taken to keep hair, skin and nails looking healthy.

It does more than support a good-looking appearance, however, considering it’s involved in many metabolic processes, including those that help us break down foods into useable nutrients and energy. Consuming enough biotin is also a way to support cardiovascular health as well as brain and nerve functions. One reason that’s true is because biotin helps the body build proteins.

If you take supplements geared towards promoting hair growth and skin health, chances are you’re consuming supplemental biotin whether you realize it or not. But what are the potential side effects of biotin? If you take too much, biotin side effects can possibly include worsened skin issues, indigestion and interactions with medications.

Find out below how to take biotin safely in a way that limits the risk for reactions.

Possible Negative Side Effects

Most people are thought to consume enough biotin from their diets, yet many still take extra in capsule form in hopes of limiting hair thinning, weak nails and dull skin.

The recommended intake of biotin is relatively low in comparison to some other nutrients, such as electrolytes (magnesium and calcium, for example) and vitamin C. This means that it can be easy to not only meet your needs, but to also exceed them.

Biotin is available in many skin and hair supplements, B complex vitamins (which include vitamin B6, vitamin B12, vitamin B2 riboflavin and vitamin B3 niacin), as well as multivitamins.

B vitamins are water-soluble, meaning any excess or unused amounts are usually eliminated through your urine pretty easily. This makes biotin toxicity, which is a dangerous overdose, rare but still possible if you take too much.

Overall biotin is safe for most adults to take. But what happens when you take too much biotin? The most common biotin side effects are:

• Changes in skin tone and texture, including acne breakouts or rashes — This may be due to your body’s ability to absorb less vitamin B5 when you’re taking high doses of biotin; B5 (pantothenic acid) is known to help fight acne, so it’s not smart to hinder your ability to absorb and utilize it.
• Skin rashes — These may form if you react poorly to certain biotin supplements, for example if you’re allergic to an ingredient or additive. Other signs of an allergy can include an itchy throat, watery eyes and congestion.
• Nausea, cramping, diarrhea or indigestion — These side effects are most likely to occur if you take supplements on an empty stomach.
• Lower vitamin C and B6 levels, which can compete with vitamin B5 for absorption.
• Changes in blood sugar levels.
• Interactions with medications, including anticonvulsants such as carbamazepine, phenobarbital, phenytoin and primidone.

Aside from what biotin supplements can do to you physically, they also have the potential to interfere with lab results in some cases. For example, there’s been some reports of inaccurate thyroid hormone tests after someone has taken high amounts of  vitamin B7.

Before having blood work done it’s best to speak with the technician or your doctor about any medications and supplements you’re taking.

How to Use Biotin Safely

Is it okay to take biotin everyday? As long as you stick to the recommended dosage, it should be.

“Recommended daily allowances” (RDAs or RDIs) of biotin have not been established due to a lack of sufficient evidence.  A general recommendation for adults is to take biotin in dosages of about 30 to 70 micrograms per day (see more below).

Some people choose to supplement with up to 10,000 micrograms of biotin per day, but this is much higher than the daily recommended value. This amount is sometimes used to treat certain conditions such as multiple sclerosis.

The proper dosage for you depends on your age and whether or not you have a biotin deficiency. According to the National Institutes of Health, the “Adequate Intake” (the level that is assumed to ensure nutritional adequacy) to obtain biotin benefits for different age groups is as follows:

• 5 micrograms daily for infants
• 6–8 micrograms daily for infants ages 7 months to 3 years old
• 12–20 micrograms daily for children ages 4–13 years old
• 25 micrograms for adolescents
• 30 micrograms for male and female adults over 19 years old
• 30 micrograms for pregnant women and 35 milligrams for women who are breastfeeding

Who needs biotin most?

Those prone to deficiencies in B vitamins are good candidates for supplementing with vitamin B7. If you fall into the groups below, or have a known biotin deficiency, talk to your healthcare provider about supplementing:

• Pregnant women
• Long-term users of certain anti-seizure medications or antibiotics
• Those who drink excessive alcohol
• Smokers
• People with intestinal malabsorption issues or serious digestive disorders, such as Crohn’s disease, celiac disease or leaky gut syndrome.
• Those with kidney disease or who have had stomach surgery.

How much biotin should you take for hair growth?

Always read directions when using any supplement, since strengths and dosages can differ from one brand to another.

Start by taking between 100 and 1,0000 mcg of biotin daily and increasing the amount of biotin foods you consume in a day. A general recommendation is try working your way up to taking about 2.5 to 3 milligrams (or 2,500 to 3,000 mcg) daily, which will cover your needs and then some.

To avoid side effects of biotin, don’t take higher amounts than necessary. And if you do notice adverse reactions, try lowering your dose, taking it only every other day, or giving yourself a break from supplementing for a few months.

One way to balance the effects of biotin is to take it with other B vitamins, such as in a B complex formula. To get the most benefits, purchase a high-quality multivitamin or supplement product that is made from real food sources and doesn’t contain fillers or possible allergens.

You can also naturally increase your intake of biotin by eating foods that are rich in this nutrient. These include: eggs, whole grains, nuts, organ meats, avocado, cauliflower, berries, fish, legumes and mushrooms.

Final Thoughts

• Biotin or vitamin B7 is usually safe to take, but it can possibly cause reactions when taken in high amounts.
• What are the side effects of too much biotin? These can include: acne, skin rashes, changes in other nutrient levels and digestive issues.
• To avoid complications, stick to dosages of about 100 micrograms per day.
• You can also increase your intake naturally from foods like whole grains, veggies, nuts, legumes, eggs and organ meats.

What are the side effects of biotin? – Drink-Drink

07/14/2022 DrinkDrinkAdmin

Contents

• Positive side effects
• Negative side effects
• What happens if you take too much biotin huh?
• Conclusion

What is biotin?

Biotin is also known as vitamin B-7. Forms fatty acids and glucose. It also helps metabolize carbohydrates and amino acids and helps break down fat in the body. These functions make biotin an important part of the energy production your body needs.

Biotin is found in many foods and drinks, including milk, carrots, salmon and nuts. It can also be taken as a supplement if needed. The recommended daily amount is 30 mcg. However, taking biotin supplements is not recommended unless recommended by a doctor.

Beneficial side effects

Biotin is an important source for energy production as well as for maintaining the functions of your body in general. Like all vitamins, your body needs biotin to stay healthy. There are several systems that biotin helps keep you healthy. Some of these include your liver, nervous system, hair, eyes, and more.

Biotin may be effective in treating certain conditions. Some of these conditions include:

• hypoglycemia
• hyperlipidemia
• glucose control in obese diabetic patients (when combined with chromium picolinate)

Some people believe that taking biotin supplements will improve the condition of your hair and nails. However, there is currently little medical evidence that this is true. More research is needed on this possible benefit of biotin.

Negative side effects

Although available as a supplement, biotin should only be taken on the advice of a physician. Most people get enough biotin from their regular diet.

Talk to your doctor about other medicines you are taking and any medical conditions you have before taking biotin. Vitamins and supplements can have a negative effect on certain medications and diseases.

There are currently no known side effects of biotin when taken as prescribed by a physician or in the normal diet.

In some cases, biotin deficiency is caused by certain dietary or other habits. Studies have found that women who smoke can increase the metabolism of biotin in the body and cause a deficiency.

Another case showed that regular consumption of raw eggs, especially egg whites, can also cause biotin deficiency. In this case, the deficiency caused a condition called biotin-sensitive limb weakness. This condition mimics quadriplegia.

Regular consumption of raw egg whites has been used in another study which has shown that it also causes biotin deficiency.

Common symptoms of biotin deficiency include:

• hair loss or thinning
• high cholesterol
• skin rashes
• heart problems

What happens if you take too much a lot of biotin?

Too much biotin is more than the recommended dose. This recommended amount includes what you naturally get from foods.

There are cases that show the negative health effects of some people who take large amounts of biotin supplements and get too much biotin. Most people get enough biotin from their regular diet. You do not need to take biotin supplements unless directed by a doctor.

Large amounts of biotin may cause false positive results in laboratory tests for thyroid disorders.

Conclusion

Your body produces enough biotin on its own with food every day. Therefore, you should not take biotin supplements unless directed to do so by a doctor. There are some rare health conditions that may cause some people to need biotin supplements on a regular basis. This can be determined by a doctor.

Supplements are not tested by the US Food and Drug Administration for purity or safety, so it’s important to buy from a manufacturer you trust.

There are not enough studies yet to determine all the side effects of taking too much biotin. However, there are case studies showing that some of the possible consequences could be severe. If you feel like you need to take biotin supplements, you should always check with your doctor first.

Health

Possible Side Effects of Taking Biotin

Vitamin B7, better known as biotin (and sometimes vitamin H), is essential for healthy skin, hair sweat glands, nerve tissue, bone marrow and nails. Biotin also promotes cell growth; metabolizing fats, carbohydrates and proteins into fuel for your muscles; and it helps your body take advantage of other B-complex vitamins. While your body can’t make biotin on its own, deficiency is rare, MedScape notes. So are the side effects.

Potential Side Effects

There are potential side effects of biotin associated with either intake or deficiency.

• 8 side effects of too much calcium supplementation
• 6 essential vitamins that promote hair growth
• Research Supported Benefits of Vitamin B12

Consumption related

Biotin is considered non-toxic. It is a water soluble vitamin, in other words your body cannot store it and any excess is flushed out of the body in the urine. Side effects from excess biotin intake are so rare that many reputable sources, including the University of Maryland Medical Center, report that they don’t exist at all. However, there are very few documented cases of side effects from taking biotin:

1. Unsubstantiated reports indicate that excessive intake of biotin may cause a marked increase in the need to urinate or unusually heavy sweating.
2. University of Maryland Medical Center reports that biotin is recommended for strengthening hair and nails; so it’s not surprising that faster growth of your hair and nails could be the result of using biotin.
3. The University of Washington Medical Center notes that some biotin users “may have side effects such as mild nausea, stomach cramps, or diarrhea.”
4. The Linus Pauling Institute of Oregon State University reports one case of “a life-threatening eosinophilic pleeuropericardial effusion in an elderly woman who took a combination of 10,000 mcg/day of biotin and 300 mg/day of pantothenic acid for two months. ” It is unclear whether this condition was caused by a combination of the two vitamins or by an entirely different factor.
5. The National Institutes of Health lists biotin as “POSSIBLY SAFE when used in the recommended amounts during pregnancy and lactation” and lists no known side effects when taken with herbs or supplements.

Deficiency Associated

Although biotin deficiency is rare, some medications can affect biotin levels, especially long-term use of antibiotics and some anticonvulsants, according to Oregon State University. Also, as unlikely as it might be, if you were to consume large amounts of raw egg whites, the National Institutes of Health (NIH) warns that you could be deficient in biotin. This is because raw egg whites contain a glycoprotein that binds to biotin and prevents it from being absorbed.

In the unlikely event of a biotin deficiency, symptoms may include:

• Scaly red rash on the face or around the genitals
• Neurological problems such as depression, lethargy, numbness and tingling of the extremities

Biotin Recommendations

Since the side effects of biotin are rarely reported, there is no recommended maximum intake of biotin. Biotin deficiency is also very rare, which is why there is no official RDA (Recommended Daily Allowance) for this vitamin. The NIH notes that the following amounts represent adequate biotin intake:

• Infants 0 to 12 months: 7 mcg per day (mcg/day)
• 1 to 3 years: 8 mcg/day
• 4 to 8 years: 12 mcg/day
• 9 to 13 years : 20 mcg/day
• 14 to 18 years: 25 mcg/day
• 18 years and older, pregnant women: 30 mcg/day.
• Breastfeeding women: 35 mcg/day.

In most cases, a balanced diet will provide at least this amount of biotin, as will most daily multivitamins. Dietary sources of biotin include whole grains, egg yolks, organ meats, marine fish, poultry, legumes, pork, and yeast.

Seek medical attention for problems

If you experience any side effects from any dietary supplement or any other medication, you should tell your healthcare provider right away. The signs can be easily recognizable and can be a combination of several factors, but if something just doesn’t feel right to you, don’t risk it.