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Quick Facts

Alopecia Areata


The Manual's Editorial Staff

Last full review/revision Jan 2021| Content last modified Jan 2021
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What is alopecia areata?

"Alopecia" means hair loss. "Areata" means occurring in patches.

Alopecia areata is the sudden loss of patches of hair without any of the obvious causes.

  • Your hair falls out in patches for no clear reason

  • Alopecia areata is common and happens most often in children and young adults

  • The hair loss is usually from the scalp or beard

  • Your fingernails may become rough and pitted

What causes alopecia areata?

Doctors think alopecia areata is an autoimmune disorder. In an autoimmune disorder your immune system mistakenly attacks part of your body. In alopecia areata, your immune system attacks your hair follicles so hair doesn't grow.

What are the symptoms of alopecia areata?

Alopecia areata causes:

  • Round patches of missing hair—patches can be small or you can lose all the hair on your scalp

You may notice short, broken hairs at the edges of the patches. You may have rough and pitted nails. There are no other symptoms, and you otherwise feel well.

How do doctors treat alopecia areata?

Alopecia areata sometimes gets better without treatment. The hair usually grows back in several months. If you have widespread hair loss, it’s less likely that your hair will regrow.  

Doctors treat alopecia areata with:

  • Corticosteroids injected at the bald spots

  • Medicine (minoxidil) applied to the bald spots

  • Sometimes, chemicals applied to the bald spot to mildly irritate it (this can cause hair growth)

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