Biotin, also known as Vitamin H, is best known for its ability to treat and improve the condition of hair and follicles. It has many benefits for the hair, skin and nails including preventing hair loss, strengthening hair and reducing breakage and increasing shine. Biotin injections have also been known to strengthen nails, encourages healthy sweat glands, increase metabolism and improve acne and eczema. Signs of a Vitamin H deficiency include dry, itchy skin, hair loss and brittle nails and hair.