Alopecia areata is an autoimmune disorder, during which hair starts to fall out in patches. In many people it may start in childhood. A family history plays a huge role in development of alopecia areata. This condition is classified as an autoimmune disorder, so the immune system mistakenly tries to attack hair follicles. Mostly it affects the scalp, but sometimes facial hair can also be involved in the process. The prevalance is equal in men and women. Treatment is usually long and as alopecia areata is a chronic condition, it can come back again, especially when there are contributing factors ( thyroid gland disorders, stress and etc.) If you have alopecia areata, you may want to see a dermatologist for a proper treatment.