Here is what America's Compounding Center says about Biotin:
"Biotin, also known as vitamin H, is a water-soluble B complex vitamin that is involved in the metabolism and conversion of food into energy. Water-soluble vitamins are not stored in the body, therefore need to be replaced regulalry in the diet. Biotin helps maintain the health of several tissues, including the eyes, skin, hair, and liver. Dietary sources of biotin include egg yolk, mushrooms, dark green vegetables, liver, and shrimp. Biotin deficiency is rare, since it is normally produced in the intestine. Biotin deficiency is usually due to chronic malabsorption, genetic disorders, or long-term therapy with total parenteral nutrition (TPN), anticonvulsants, or antibiotics. Symptoms associated with biotin deficiency include stomach upset, fatigue, muscle pain, hair loss, anemia, mood changes, and dry skin or a grayish discoloration of the skin. The UMDF recommends taking 2.5-10 mg of biotin daily. Biotin supplementaion has been associated with stomach upset, but is generally well-tolerated."