Alopecia Areata


What Is It?

Alopecia areata is a skin disorder that causes hair loss, usually in patches, most often on the scalp. Usually, the bald patches appear suddenly and affect only a limited area. The hair grows back within 12 months or less. For some people, however, the problem can last longer and be more severe, causing total baldness (alopecia totalis) or total loss of body hair (alopecia universalis).

The cause of alopecia areata is probably an autoimmune reaction. This means the body’s immune system incorrectly attacks the body’s own cells. In the case of alopecia areata, the cells under attack are in the hair follicles (structures that grow hair), especially follicles within the scalp.

Genetic (inherited) factors may play a role, too, particularly when the disorder strikes those under age 30. Almost 40 percent of people under 30 with alopecia areata have at least one family member who has been diagnosed with the same disorder.

The risk of developing alopecia areata is unusually high in people who have asthma, hay fever, thyroid disease, vitiligo (a condition in which patches of skin lose their color), pernicious anemia and Down syndrome.

Although experts once believed episodes of alopecia areata could be triggered by stress, newer research has failed to prove that stress is a factor.

Approximately 1 percent to 2 percent of people in the United States develop alopecia areata at some time during their lives. In about 60 percent of cases, the first episode of hair loss occurs before age 20 and is followed by hair regrowth. However, it’s common for the problem to come back, and new bald patches can develop at the same time older ones are regrowing hair.


In its most common form, alopecia areata causes small round or oval patches of baldness on the scalp. The area of bald skin looks smooth and normal. In most cases, there are no other scalp symptoms. Occasionally, there is mild itching, tingling, tenderness or a burning sensation in the affected area. Some people with alopecia areata also have abnormalities in the surface of their fingernails, such as tiny pits or dents, grooves, superficial splitting or an abnormal area of redness.

In rarer, more severe forms of the disorder, hair loss can involve the entire scalp or the entire body, including the eyebrows, eyelashes, beard, underarm hair and pubic hair (hair around the genitals).


Your doctor may suspect that you have alopecia areata based on your symptoms and, in some cases, your family history of the disorder. To look for further evidence, your doctor will examine your scalp and pull gently on the hairs near the edge of the bald area. If these hairs come out very easily, the doctor will inspect them for structural abnormalities of the root or shaft. In some cases, a small skin biopsy of your scalp may confirm the diagnosis. In a biopsy, a small piece of skin is removed and examined in a laboratory.

Expected Duration

In most small patches of alopecia areata, the hair regrows within six to 12 months. However, it’s common for the problem to happen again.


Alopecia areata cannot be prevented.


Although there is no permanent cure for alopecia areata, there are ways to short-circuit the body’s autoimmune reaction in the scalp and encourage hair regrowth. Options include:

  • Cortisone cream applied on the bald patches or cortisone solution injected into the bald patches to suppress the immune reaction
  • Immunotherapy using chemicals such as diphenylcyclopropenone (also called diphencyprone or DCP) or squaric acid dibutyl ester (SADBE) on the scalp that can produce an allergic reaction, which may neutralize the turned-on immune cells.
  • Topical minoxidil (Rogaine), which can increase hair growth by accelerating the speed of the natural hair cycle, and may increase the diameter of hairs that begin to grow.
  • Anthralin (Drithocreme, Dritho-Scalp, Micanol) applied to the scalp, which causes a scalp irritation that may stimulate early hair regrowth, and can be used with minoxidil
  • Psoralen and ultraviolet A phototherapy (controlled exposure of the affected skin to ultraviolet light)
  • A short course of corticosteroids (such as prednisone) by mouth, or rarely, intravenously (through a vein) for adult patients with extensive hair loss

Your treatment depends on several factors, including your age (some treatments are only for adults), the amount of your hair loss and your willingness to deal with any treatment-related discomfort or side effects.

If you have mild hair loss, you may choose to simply modify your hairstyle or wear a hairpiece until the bald area fills in.

If you lost a large amount of hair on your scalp, you may choose to wear a wig or hairpiece until your treatment starts to work. If you have an obvious loss of eyebrow hair, you may choose to have injections of tiny dots of colored pigments into the eyebrow area (a procedure called dermatography). If you find it hard to cope with the change in your appearance, mention it to your doctor or seek advice from a mental health professional.

When To Call A Professional

Make an appointment to see your doctor if:

  • You suddenly develop a bald spot on your scalp
  • Your hair stylist tells you that your hair is thinning, or that you have small bald areas
  • You have lost your eyebrows or eyelashes, your beard is thinning, or you have noticeably less hair on your underarms or pubic area


In more than 90 percent of cases, hair grows back and fills the bald spot within one year, even without treatment. However, recurrences are common, and most people have several episodes of the disorder during a lifetime. Only about 7 percent of people develop severe, long-term forms of the illness that produce large areas of hair loss with little hair regrowth.

Johns Hopkins patient information

Last revised:

Diseases and Conditions Center

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All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.