Alopecia areata refers to a disease of the dermal accessory organs characterized by sudden localized and macular loss of hair. The causative reason is unknown and the mental factor is often the reason to induce and aggravate the condition. Someone believes that it is also related to heredity and autoimmunity. This disease belongs to the category of "Hair Loss". It is mostly related to unhappy mood and deranged mind, leading to consumption of heart blood, or deficiency of the liver and kidney, and insufficiency of yin and blood, or deficiency of blood and qi, and weakness of interstitial space, leading to opening of the hair pores, or invasion of pathogenic wind, excessive wind and blood dryness, leading to malnutrition of the hair. This disease can also be caused by obstruction of the meridians and collaterals due to stagnation, resulting in inability for new hair to grow.