Alopecia Areata is considered an autoimmune disease..

Our immune system makes white blood cells and antibodies which attacks on viruses, bacteria, and other foreign bodies. If you have an auto-immune disease, your immune system can misunderstand part or parts of your body as foreign body. In people with alopecia areata, many white blood cells gather around the affected hair follicles which are mistaken as foreign body. This causes some mild inflammation and by this hairs becoming 'weak' and fall out to cause the bald patches. 

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Minoxidil Prevents Hair Loss.. 

 It is an anti balding drug and the only FDA approved drug considered safe for women. Researches world over although could not tell exactly why it works however they certainly have shown that minoxidil solution applied topically is very beneficial in preventing hair loss.

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