Alopecia Areata is an autoimmune condition in which hair is lost in round patches that can vary in size. Many times they are about the size of a nickel or quarter. Some people will have only a few patches of hair loss and in some there might be more extensive loss.
In an autoimmune condition it is believed that the body’s immune system mistakes some part of the body for an invading infection or a disease. Instead of having the normal response of attacking the invader, the immune system mistakenly and randomly attacks some part of the body. This is also thought to be the same response as seen in Alopecia Totalis.
It is unclear what exactly causes Alopecia Areata. Some believe that a virus, something in the person’s home environment, or possibly the work environment may be the potential trigger for the mistaken invasion of the immune system. In many instances, the hair will grow back over a period of time without any further reoccurrence or treatment.