Health Care Professional Information

Scientific Name
Cis-hexahydro-2-oxo-1H-thieno[3,4-d]-imidazole-4-valeric acid
Common Name

Vitamin H, coenzyme R, D-Biotin, W Factor

Clinical Summary

An important coenzyme in carbohydrate and lipid metabolism, biotin has been claimed to treat brittle finger nails, acne, seborrhoeic dermatitis, hair fragility, and alopecia.
Infants who died from sudden infant death syndrome (SIDS) were found to have significantly lower levels of biotin in their livers; however, evidence that biotin deficiency contributes to SIDS is lacking (1). Deficiency of biotinidase, an enzyme that converts biotin into its active form, has been implicated in myelopathy (13), epileptic encephalopathy (14), and spastic tetraparesis (15) in children.
A small randomized controlled trial showed that biotin was no more effective than placebo in the treatment of seborrheic dermatitis in infants (2).
Biotin supplementation may be effective in strengthening brittle nails (3). Preliminary data suggest biotin may have beneficial effects in patients with severe diabetic peripheral neuropathy (4), and when combined with chromium, it may be effective as an adjunct therapy to improve glycemic control in patients with type 2 diabetes (5).

Food Sources

Liver, kidney, eggs, soya beans, peanuts, wholegrain cereals, and dairy products.

Purported Uses
  • Acne
  • Alopecia
  • Brittle nails
  • Diabetic neuropathy
  • Infantile seborrheic dermatitis
  • Thyroid disorder
Mechanism of Action

Biotin is an essential part of carbohydrate and lipid metabolism via transporting carboxyl units and fixing carbon dioxide. It is commonly found in a wide variety of foods. Biotin is converted into the active form by an enzyme, biotinidase. It is also synthesized in the intestine by bacteria. Patients who are deficient in biotinidase or who have malabsorption syndrome may develop biotin deficiency. Although biotin deficiency is rare, symptoms include anorexia, nausea, vomiting, dermatitis, somnolence, seizures, ataxia, and increase in serum cholesterol levels and bile pigments (1). Biotin may also be deficient, inactive, or unavailable in patients with diabetes. Therefore, it is suggested that biotin supplementation may be effective against diabetic peripheral neuropathy (4); in neurons, biotin induces microtubule formation (7) and biotin deficiency slows myelination (8). However, biotin supplementation may reduce the activity of interleukins and interferons and reduce the number of leukocytes (9).


Biotin is rapidly absorbed from the gastrointestinal tract through facilitated transport and passive diffusion. Absorption is greatest in the jejunum. Certain anticonvulsant drugs inhibit biotin transport in the human intestine by competitively binding with the human brush border membrane vesicles.

Biotin binds to plasma proteins.

Excess biotin is excreted via urine. It also appears in breast milk.
(1) (10)

  • Ingestion of large amounts of raw egg whites (1) and long-term anticonvulsant therapy (11) can induce biotin deficiency.
Adverse Reactions
  • One case of eosinophilic pleuropericardial effusion was reported in a woman following concomitant use of biotin and pantothenic acid (vitamin B5) (6).
Herb-Drug Interactions

Long term use of certain anticonvulsant drugs may accelerate biotin catabolism, which can theoretically cause biotin deficiency (11).

Herb Lab Interactions
  • Free Thyroxine (FT4): There is a report of a false-high FT4 on the assay by the Boehringer Mannheim ES 700 analyzer attributed to high serum biotin levels in a neonate (12).
  • Thyroid Stimulating Hormone (TSH): There is a report of a false-low TSH on the assay by the Boehringer Mannheim ES 700 analyzer attributed to high serum biotin levels in a neonate (12).
Dosage (Inside MSKCC Only)
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  1. Mason P. Dietary Supplements. London: Pharmaceutical Press; 2001.
  2. Keipert JA. Oral use of biotin in seborrhoeic dermatitis of infancy: a controlled trial. Med J Aust. 1976;1:584-5.
  3. Hochman LG, Scher RK, Meyerson MS. Brittle nails: response to daily biotin supplementation. Cutis 1993;51:303-5.
  4. Koutsikos D, Agroyannis B, Tzanatos-Exarchou H. Biotin for diabetic peripheral neuropathy. Biomed.Pharmacother. 1990;44:511-4.
  5. Albarracin CA, Fuqua BC, Evans JL, et al. Chromium picolinate and biotin combination improves glucose metabolism in treated, uncontrolled overweight to obese patients with type 2 diabetes. Diabetes Metab Res Rev. Jan-Feb 2008;24(1):41-51.
  6. Debourdeau PM, et al. Life-threatening eosinophilic pleuropericardial effusion related to vitamins B5 and H. Ann.Pharmacother. 2001;35:424-6.
  7. Braguer D, Gallice P, Yatzidis H, et al. Restoration by biotin of the in vitro microtubule formation inhibited by uremic toxins. Nephron. 1991;57(2):192-196.
  8. Desai S, Ganesan K, Hegde A. Biotinidase deficiency: a reversible metabolic encephalopathy. Neuroimaging and MR spectroscopic findings in a series of four patients. Pediatr Radiol. Aug 2008;38(8):848-856.
  9. Zempleni J, Helm RM, Mock DM. In vivo biotin supplementation at a pharmacologic dose decreases proliferation rates of human peripheral blood mononuclear cells and cytokine release. J Nutr 2001;131:1479-84.
  10. Said HM, Redha R, Nylander W. Biotin transport in the human intestine: inhibition by anticonvulsant drugs. Am J Clin Nutr 1989;49:127-31.
  11. Mock DM, et al. Disturbances in biotin metabolism in children undergoing long-term anticonvulsant therapy. J Pediatr.Gastroenterol.Nutr 1998;26:245-50.
  12. Henry JG, Sobki S, Arafat N. Interference by biotin therapy on measurement of TSH and FT4 by enzyme immunoassay on Boehringer Mannheim ES700 analyser. Ann.Clin Biochem. 1996;33 (Pt 2):162-3.
  13. Raha S, Udani V. Biotinidase deficiency presenting as recurrent myelopathy in a 7-year-old boy and a review of the literature. Pediatr Neurol. 2011 Oct;45(4):261-4.
  14. Singhi P, Ray M. Ohtahara syndrome with biotinidase deficiency. J Child Neurol. 2011 Apr;26(4):507-9.
  15. Komur M, Okuyaz C, Ezgu F, Atici A. A girl with spastic tetraparesis associated with biotinidase deficiency. Eur J Paediatr Neurol. 2011;5(6):551-3.

Consumer Information

How It Works

Bottom Line: Some studies suggest biotin may help to strengthen brittle nails and improve peripheral neuropathy (a disorder of the peripheral nerves) in diabetics. More studies are needed to confirm such effects.

Biotin is an important coenzyme involved in carbohydrate (sugar) and lipid (fat) metabolism. It is made in the intestines and is commonly found in a variety of foods. Consuming large amounts of egg whites or taking anticonvulsant (antiepileptic) drugs may lead to biotin deficiency, although this is rare. Patients with diabetes may have a greater chance of being biotin deficient. However, biotin supplementation may weaken the activity of immune signals (i.e., interleukins and interferons) and reduce the number of white blood cells.

Purported Uses
  • To treat diabetic peripheral neuropathy
    A small clinical study supports this claim; however, larger studies are needed to confirm the effects.
  • To treat brittle nails
    A small survey indicates that biotin may be effective; further studies are needed.
  • To treat infantile seborrheic dermatitis (a skin disorder prevalent in the oily areas of the skin, resulting in itchy, scaly skin)
    A small randomized trial showed that biotin is no more effective than placebo in treating seborrheic dermatitis in infants.
Do Not Take If
  • You are a long term user of anticonvulsant drugs: They may accelerate biotin catabolism, which can theoretically cause biotin deficiency.
Side Effects
  • Eosinophilic pleuropericardial effusion (inflammation and filling of the lining around the heart and lungs with fluid) was reported in a woman who took biotin along with Vitamin B5.
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