Biotin is a water-soluble B vitamin,[2] also called vitamin B7 and formerly known as vitamin H or coenzyme R. It is involved in a wide range of metabolic processes, both in humans and in other organisms, primarily related to the utilization of fats, carbohydrates, and amino acids. Subclinical deficiency can cause mild symptoms, such as hair thinning or skin rash typically on the face. Neonatal screening for biotinidase deficiency began in the United States in 1984, with many countries testing for this disorder at birth. Individuals born prior to 1984 are unlikely to have been screened, obscuring the true prevalence of the disorder.
Biotin is an important component of enzymes involved in metabolizing fats and carbohydrates, influencing cell growth, and affecting amino acids involved in protein synthesis. Biotin assists in various metabolic reactions involving the transfer of carbon dioxide. It may also be helpful in maintaining a steady blood sugar level. Biotin is often recommended as a dietary supplement for strengthening hair and nails, though scientific data supporting these outcomes are weak. Nevertheless, biotin is found in many cosmetics and health products for the hair and skin.
Deficiency symptoms include:
Brittle and thin fingernails, Hair loss (alopecia),Conjunctivitis, Dermatitis in the form of a scaly, red rash around the eyes, nose, mouth, and genital area.
Neurological symptoms in adults, such as depression, lethargy, hallucination, and numbness and tingling of the extremities.
The neurological and psychological symptoms can occur with only mild deficiencies. Dermatitis, conjunctivitis, and hair loss will generally occur only when deficiency becomes more severe. Individuals with hereditary disorders of biotin deficiency have evidence of impaired immune system function, including increased susceptibility to bacterial and fungal infections. Pregnant women tend to have a higher risk of biotin deficiency. Nearly half of pregnant women have abnormal increases of 3-hydroxyisovaleric acid, which reflects reduced status of biotin.
Kidney dialysis: People receiving kidney dialysis may need extra biotin. Check with your health care provider.

Side Effects & Safety:
Biotin is LIKELY SAFE for most people when taken by mouth appropriately or when applied to the skin as cosmetic products that contain 0.0001% to 0.6% biotin. Biotin is well tolerated when used at recommended dosages. It is POSSIBLY SAFE when given as a shot.

Pregnancy and breast-feeding: Biotin is POSSIBLY SAFE when used in recommended amounts during pregnancy and breast-feeding.
Interactions:
We currently have no information for BIOTIN Interactions
Dosing:
The following doses have been studied in scientific research:
ADULTS:
•General: There is no recommended dietary allowance (RDA) established for biotin. The adequate intakes (AI) for biotin are 30 mcg for adults over 18 years and pregnant women, and 35 mcg for breast-feeding women.
•Biotin deficiency: Up to 10 mg daily has been used.
CHILDREN:
BY MOUTH: •General: There is no recommended dietary allowance (RDA) established for biotin. The adequate intakes (AI) for biotin are 7 mcg for infants 0-12 months, 8 mcg for children 1-3 years, 12 mcg for children 4-8 years, 20 mcg for children 9-13 years, and 25 mcg for adolescents 14-18 years.