Practice Essentials
Deficiency of biotin, a water-soluble B vitamin, may occur from nutritional causes, but more commonly results from deficiencies of enzymes involved in biotin homeostasis (e.g. biotinidase deficiency). Affected patients can present with abnormal skin and hair changes, metabolic and neurologic abnormalities. In severe cases, without treatment, coma and death may ensue. Early detection and treatment with pharmacologic doses of biotin are important to prevent the development of irreversible complications. Marginal biotin deficiency has been demonstrated in pregnancy and lactation, but the clinical significance is uncertain. Biotin supplements have been promoted to improve skin, hair and nail health; however robust evidence for their efficacy is lacking. It is important to be aware that intake of biotin supplements may lead to interference with certain laboratory tests leading to false positive or false negative results. High-dose biotin has been found to be helpful in certain neurological conditions (e.g. multiple sclerosis); however, the mechanism of action is uncertain