Alopecia areata is a type of hair loss that occurs when your immune system mistakenly attacks hair follicles. The damage to the follicle is usually not permanent. Experts do not know why the immune system attacks the follicles. Alopecia areata is most common in people younger than 20, but children and adults of any age may be affected. Women and men are affected equally.
Alopecia areata usually begins when clumps of hair fall out, resulting in totally smooth, round hairless patches on the scalp. In some cases the hair may become thinner without noticeable patches of baldness, or it may grow and break off, leaving short stubs. In rare cases, complete loss of scalp hair and body hair occurs. When alopecia areata results in patches of hair loss, the hair usually grows back in a few months.
Male-pattern baldness, don't need treatment because they're a natural part of ageing and don't pose a risk to your health and if the hair loss is due to cosmetic reasons then two medications called finasteride and minoxidil can be used. These treatments don't work for everyone and only work for as long as they're continued. Minoxidil can also be used to treat female-pattern baldness. This involves stimulating hair growth by causing an intentional allergic reaction in the affected areas of skin.