Quick Facts: Alopecia Areata - Merck Manuals Consumer Version

Q: 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.

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What is alopecia areata?

What causes alopecia areata?

What are the symptoms of alopecia areata?

How do doctors treat alopecia areata?

Hair Disorders

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Inability of the body to absorb vitamin B12 or folate from the digestive tract
Lack of vitamin B12 or folate in the diet
Use of certain antidepressant drugs called selective serotonin reuptake inhibitors (SSRIs)
Use of certain drugs to treat cancer

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Last full review/revision Apr 2019

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"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

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.

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.

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)

Generic Name	Select Brand Names
minoxidil	ROGAINE

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