Common Names
- Vitamin H
- Vitamin B7
- Coenzyme R
- D-Biotin
- W Factor
For Patients & Caregivers
Tell your healthcare providers about any dietary supplements you’re taking, such as herbs, vitamins, minerals, and natural or home remedies. This will help them manage your care and keep you safe.
What is it?
Biotin is a vitamin your body needs to process sugar and fats. It’s found in foods such as organ meats (like liver or kidney), eggs, almonds, soy beans, peanuts, wholegrain cereals, brewer’s yeast, and vegetables.
Biotin supplements are available as pills, soft gels or gummies. They are taken alone or combined with other vitamins for healthy skin, nails, and hair.
What are the potential uses and benefits?
Biotin is used to:
- Make brittle nails stronger
- Make hair healthy
- Treat skin rash
- Treat disability due to multiple sclerosis (a disease of the brain and spinal cord)
- Treat nerve pain due to diabetes
While biotin has many uses, more research is needed to prove that it helps with these issues.
Biotin is generally safe. But dietary supplements can interact with some medications and affect how they work. For more information, read the “What else do I need to know?” section below.
What are the side effects?
No side effects have been reported.
What else do I need to know?
It’s important to talk to your healthcare provider before taking biotin supplements. They can cause incorrect results on some lab tests. This can affect your care by:
- Making it harder for your doctor to diagnose a disorder or disease that you may have
- Not showing how you’re responding to a treatment
- Making you go through additional testing
For Healthcare Professionals
Scientific Name
Clinical Summary
Biotin is an essential B vitamin that acts as an important coenzyme in carbohydrate and lipid metabolism. It is often taken alone or in combination with other vitamins for skin, nail, and hair health. It is also thought to benefit patients with diabetes and neuromuscular disorders.
Biotin is abundant in foods including meat, vegetables, and eggs. True deficiency is rare but can be caused by a genetic disorder (13) or malabsorption syndrome. Long-term use of certain anticonvulsant drugs can also induce biotin deficiency (11). These can be treated with supplementation.
Low serum levels of biotin have been associated with hair loss in some women (16), but evidence on biotin for hair growth or strengthening brittle nails is limited (3) (23) (24) (41).
Although preliminary data found benefit with high-dose biotin for multiple sclerosis (17), a larger well-designed trial did not, but did find the potential for adverse consequences stemming from inaccurate lab test results (37). A review also cited insufficient evidence to support this use (30).
Exploratory studies suggest biotin may benefit patients with severe diabetic peripheral neuropathy (4), improve glycemic control when taken with chromium (5), depression in patients undergoing methadone maintenance treatment when taken in the form of a multivitamin (42), and electrophysiological variables in those with demyelinating neuropathies (43). Randomized trials are needed to validate these observations. Some case reports suggest biotin may help reduce chemotherapy-related skin rash (18), but overall evidence is lacking to support its use for dermatological disorders (31).
Cases of inaccurate diagnostic test results have been linked to biotin supplement consumption. The American Association of Clinical Chemistry has issued a guidance document to help identify and address biotin interference in lab testing (32), and newer-generation assays now prevent biotin interference for hsTnT and TSH testing (38).
Food Sources
Liver, kidney, eggs, almonds, sweet potato, soy beans, peanuts, wholegrain cereals, brewer’s yeast, dairy products
Purported Uses and Benefits
- Brittle nails
- Hair loss
- Dermatitis
- Multiple sclerosis
- Diabetic neuropathy
Mechanism of Action
Biotin is an essential component in carbohydrate and lipid metabolism. It is converted to the free active form by the enzyme biotinidase (1).
Studies have shown that biotin induces microtubule formation in neurons (7), and deficiency slows myelination (8), which may result in neuropathy. Biotin may also reduce the activity of interleukins and interferons, decreasing the number of leukocytes (9).
Adverse Reactions
Although biotin is generally safe, supplementation has been reported to interfere with certain lab tests, which may mask disease states, overestimate response to therapies, or subject patients to additional unnecessary diagnostic procedures (29). Newer-generation assays now prevent biotin interference for hsTnT and TSH testing (38).
Case Reports
Missed diagnosis of heart disease due to high intake of biotin: A patient death was related to false low troponin test results that were due to high intake of biotin (22). Additional reports have shown the susceptibility of cardiac troponin assays to biotin interference at levels achievable with over-the-counter supplements (28).
Tardive reactivation of progressive multiple sclerosis: In a 41-year-old patient suffering from primary progressive MS following treatment with high doses of biotin. His expanding disability status worsened along with a symptomatic new lesion on brain MRI, suggesting tardive inflammatory reactivation likely due to biotin (33).
TSH aberrations in the setting of immunotherapy: In a 68-year-old woman with hypothyroidism after initiating checkpoint blockade therapy while on biotin supplements. The patient was initiated on levothyroxine with subsequent dose increases that led to symptom resolution (39).
Hyperthyroidism: In a 64-year-old male with a history of multiple sclerosis following intake of biotin. His lab results returned to normal values after discontinuing biotin (44). Elevated free thyroxine (FT4) and free triiodothyronine (FT3) levels were reported in a 46-year-old male with Grave’s disease after high-dose biotin intake. His lab results returned to normal after assays for FT3 and FT4 were changed from those containing streptavidin-biotin complexes to biotin-free ones (45).
Herb Lab Interactions
Immunoassay interference caused by high-dose biotin supplementation: Incorrect test results during routine follow-up of a 54-year-old female patient with progressive multiple sclerosis and Hashimoto’s thyroiditis (29).
Inaccurate troponin test results: Due to consumption of high dose biotin (22), although newer-generation assays now prevent biotin interference for hsTnT and TSH testing (38).
Free Thyroxine and Thyroid Stimulating Hormone (FT4/TSH) assay: False-high values were attributed to high serum biotin levels in a neonate (12). Newer-generation assays now prevent biotin interference for TSH testing (38).
Qualitative urine hCG tests: Biotin supplementation may cause an invalid test result with some pregnancy tests (25).
Immunoassay interference: Biotin taken in moderate to high doses can result in either false-high or -low values (19).
Clinically significant lab errors: In a 67-year-old female with a history of multiple endocrine issues following biotin supplementation. Blood tests showed low TSH, low PTH, and mildly elevated calcium levels, which normalized after discontinuing biotin (34). Newer-generation assays now prevent biotin interference for TSH testing (38).
Thyroid function tests consistent with hyperthyroidism and a positive radioactive iodine uptake (RAIU) scan: In a 34-year-old female with a history of anxiety and depression, while taking biotin supplements. Her labs normalized after stopping biotin (35).
Erroneous elevations of results in some commercial serum 25-hydroxyvitamin d (25OHD) assays: Due to biotin supplementation (36).
Elevated testosterone due to interference of laboratory immunoassay: In a 15-year-old girl with unusual presentation of Denys-Drash syndrome, with end stage renal failure, severe genital abnormalities, signs of hyperandrogenism, and suspected dysgenetic gonads. Her clinical history revealed that she consumed biotin (40).