Medically reviewed by Dr. A.M. van Coevorden, dermatologist
Alopecia areatasudden, round bald patches from an autoimmune reaction
Alopecia areata is hair loss in which round or oval bald patches appear suddenly, usually on the scalp but sometimes in the eyebrows, beard, armpits or pubic area. It is an autoimmune reaction: the immune system turns against the hair roots. You do not feel ill, but the baldness can have psychological effects.
What is alopecia areata?
In alopecia areata bald patches appear suddenly in areas where hair grows, usually round or oval. It mainly occurs on the scalp, but also in the eyebrows, beard, armpits and pubic area. You do not feel ill, although the baldness can cause insecurity or make social contact harder.
How do you get alopecia areata?
Why someone develops it is unknown. The cause probably lies in the immune system, which mistakenly turns against the body's own hair roots: an autoimmune reaction. Alopecia areata is more common in people who already have an autoimmune disease, and in people prone to eczema, asthma or hay fever.
What symptoms does it cause?
You recognise alopecia areata by suddenly appearing round or oval bald patches. Sometimes you do not notice it yourself and it is spotted by the hairdresser or others. The nails can sometimes look different too. In severe cases hair falls out in large clumps, sometimes evenly across the whole scalp, and in rare cases all scalp or body hair falls out.
Is alopecia areata contagious?
No. Alopecia areata is not contagious.
How is the diagnosis made?
The doctor immediately sees whether there are one or more bald patches. Evenly spread hair loss is harder to assess, and the doctor will want to rule out another hair disease, often with a hair-pull test to judge how firmly the hairs are attached. Sometimes hairs are examined under the microscope or a small piece of skin is removed for examination.
What treatments are available?
Hair growth usually recovers on its own within a few months to years, so treatment is not needed; still, many people find it hard to wait. To speed recovery there are a few options.
Corticosteroids suppress the wrong immune reaction in the bald patches. They can be injected into the patch or applied as an ointment, cream or lotion, and are used mainly for small patches; the hairs start growing again a few weeks later. The skin can thin locally, which usually recovers. For extensive alopecia areata, corticosteroid tablets are sometimes given, but their effect has never been convincingly shown and internal side effects can occur.
Topical immunotherapy is used in severe cases: you are made allergic to a substance (usually diphencyprone), after which the bald patches are treated with it. The mild allergic reaction seems to encourage the hair roots. Possible side effects are itch, swollen neck lymph nodes and sometimes pigment changes. Not all dermatologists use it. Other irritant agents are azelaic acid cream and minoxidil lotion.
Can alopecia areata be cured?
The course is hard to predict. Usually the hair grows back on its own, over a few months to years; the new hairs are sometimes white at first and later regain their normal colour. Hair can return in one spot while new bald patches appear elsewhere, and the condition can recur years later. Small bald patches usually recover fully. In extensive alopecia areata, with loss of all scalp or body hair, hair growth usually does not return permanently. Recovery is less likely if the condition began in childhood, if there are other autoimmune diseases, or with a tendency to eczema, asthma or hay fever.
What can you do yourself?
For extensive baldness you can consider a wig or hairpiece; health insurers cover this partly from basic insurance. A diet or vitamin supplements do not help. If you have psychological or social problems from the hair loss, discuss this with your doctor or someone around you.
Frequently asked questions about alopecia areata
Will my hair come back?
Usually yes; small bald patches often recover fully, over a few months to years. In very extensive forms hair often does not return permanently.
Is alopecia areata contagious?
No. It is an autoimmune reaction against your own hair roots and does not pass from person to person.
What is the cause?
Probably the immune system turning against the hair roots by mistake. It is more common with autoimmune diseases and with a tendency to eczema, asthma or hay fever.
Do vitamins or a diet help?
No. A diet and vitamin supplements do not make the hair grow.
What can the doctor do?
For small patches, corticosteroids to suppress the immune reaction, and for severe forms sometimes topical immunotherapy.