Overview of Alopecia Areata
Alopecia areata is a disease that happens when the immune system attacks hair follicles and causes hair loss. Hair follicles are the structures in skin that form hair. While hair can be lost from any part of the body, alopecia areata usually affects the head and face. Hair typically falls out in small, round patches about the size of a quarter, but in some cases, hair loss is more extensive. Most people with the disease are healthy and have no other symptoms.
The course of alopecia areata varies from person to person. Some have bouts of hair loss throughout their lives, while others only have one episode. Recovery is unpredictable too, with hair regrowing fully in some people but not others.
There is no cure for alopecia areata, but there are treatments that help hair grow back more quickly. There are also resources to help people cope with hair loss.
Who Gets Alopecia Areata?
Anyone can have alopecia areata. Men and women get it equally, and it affects all racial and ethnic groups. The onset can be at any age, but most people get it in their teens, twenties, or thirties. When it occurs in children younger than age 10, it tends to be more extensive and progressive.
If you have a close family member with the disease, you may have a higher risk of getting it, but for many people, there is no family history. Scientists have linked a number of genes to the disease, which suggests that genetics play a role in alopecia areata. Many of the genes they have found are important for the functioning of the immune system.
People with certain autoimmune diseases, such as psoriasis, thyroid disease, or vitiligo, are more likely to get alopecia areata, as are those with allergic conditions such as hay fever.
It is possible that emotional stress or an illness can bring on alopecia areata in people who are at risk, but in most cases, there is no obvious trigger.
Types of Alopecia Areata
There are three main types of alopecia areata:
- Patchy alopecia areata. In this type, which is the most common, hair loss happens in one or more coin-sized patches on the scalp or other parts of the body.
- Alopecia totalis. People with this type lose all or nearly all of the hair on their scalp.
- Alopecia universalis. In this type, which is rare, there is a complete or nearly complete loss of hair on the scalp, face, and rest of the body.
Symptoms of Alopecia Areata
Alopecia areata primarily affects hair, but in some cases, there are nail changes as well. People with the disease are usually healthy and have no other symptoms.
Alopecia areata typically begins with sudden loss of round or oval patches of hair on the scalp, but any part of the body may be affected, such as the beard area in men, or the eyebrows or eyelashes. Around the edges of the patch, there are often short broken hairs or “exclamation point” hairs that are narrower at their base than their tip. There is usually no sign of a rash, redness, or scarring on the bare patches. Some people say they feel tingling, burning, or itching on patches of skin right before the hair falls out.
When a bare patch develops, it is hard to predict what will happen next. The possibilities include:
- The hair regrows within a few months. It may look white or gray at first but may regain its natural color over time.
- Additional bare patches develop. Sometimes hair regrows in the first patch while new bare patches are forming.
- Small patches join to form larger ones. In rare cases, hair is eventually lost from the entire scalp, called alopecia totalis.
- There is a progression to complete loss of body hair, a type of the disease called alopecia universalis. This is rare.
In most cases, the hair regrows, but there may be subsequent episodes of hair loss.
The hair tends to regrow on its own more fully in people with:
- Less extensive hair loss.
- Later age of onset.
- No nail changes.
- No family history of the disease.
Nail changes such as ridges and pits occur in some people, especially those who have more extensive hair loss.
Causes of Alopecia Areata
In alopecia areata, the immune system mistakenly attacks hair follicles, causing inflammation. Researchers do not fully understand what causes the immune attack on hair follicles, but they believe that both genetic and environmental (non-genetic) factors play a role.
Diagnosis of Alopecia Areata
Doctors usually diagnose alopecia areata by:
- Examining the areas where the hair has been lost and looking at your nails.
- Examining your hair and hair follicle openings using a handheld magnifying device.
- Asking about your medical and family history.
Other health conditions can cause hair to fall out in the same pattern as alopecia areata. To determine if another condition is causing the hair loss, your doctor may order blood tests or a skin biopsy.
Treatment for Alopecia Areata
For many people, hair grows back without any type of treatment. For people with milder cases, no treatment may be needed. Some people with severe cases opt to forego treatment as well, and may instead consider products that conceal hair loss, such as hairpieces or wigs.
If you choose to seek treatment, your doctor will take into account your age and the extent of hair loss when making a treatment plan. While there are no drugs that have been approved by the U.S. Food and Drug Administration for alopecia areata, medications that have been approved for other conditions may be used to treat it. These include corticosteroids, immunosuppressants, and other medications that stimulate hair regrowth. The main goal of therapy is to stop the immune system attack on hair follicles and to stimulate the regrowth of hair.
Who Treats Alopecia Areata?
Alopecia areata is treated by:
- Dermatologists, who specialize in conditions of the skin, hair, and nails.
Other specialists who may be involved in your care include:
- Mental health professionals, who can help with the psychosocial challenges caused by having a medical condition.
- Primary care doctors, such as family physicians or internal medicine specialists, who coordinate care between the different health providers and treat other problems as they arise.
Living With Alopecia Areata
Alopecia areata does not cause physical disability, but it may affect your sense of well-being. There are many things you can do to cope with the effects of this disease, including:
- Learn as much as you can about the disease, and talk with others who are dealing with it. Having a support network can help you deal with difficult times.
- Visit a mental health professional if emotional problems arise. People with alopecia areata may have higher levels of stress, and depression and anxiety are more common in people with the disease.
Protect bare skin and stay comfortable.
- Use sunscreens for any bare areas.
- Wear wigs, hairpieces, hats, or scarves to protect your scalp from the sun and to keep the head warm.
- Wear eyeglasses or sunglasses to protect your eyes from sun and dust if you have lost hair from your eyebrows or eyelashes.
Consider cosmetic solutions.
- Wear a wig, hairpiece, or bandana to cover up hair loss. Alternatively, some people choose to shave their heads to mask patchy hair loss.
- Use fake eyelashes or apply stick-on eyebrows if you lose hair from your eyelashes or eyebrows. Makeup or tattoos can also disguise loss of eyebrow hair.
People with alopecia areata have a higher risk of certain diseases such as thyroid disease, atopic dermatitis, or other autoimmune diseases, so it is important to visit your primary care doctor regularly. The sooner these diseases are diagnosed, the easier they are to control.
Research Progress Related to Alopecia Areata
Investigators at research institutions across the country, many supported by the National Institutes of Health, are working to understand what causes alopecia areata and to develop new treatment strategies.
Following are examples of studies that are ongoing.
- Investigators are working to identify the immune abnormalities that underlie alopecia areata, and to find ways to lessen them. These studies may also uncover biomarkers that researchers can use to measure disease severity and the effectiveness of experimental therapies.
- Genetics play a role in who gets alopecia areata, but only a few disease genes have been found so far. Investigators are working to identify additional disease genes by comparing the genomes of people with alopecia areata to controls. This knowledge may help them better understand what causes the disease, and may lead to new treatment approaches.
- In addition to genetics, researchers believe that environmental factors play a part in alopecia areata. Scientists are investigating whether factors such as stress, diet, or the microbiome (the collection of all the microbes that inhabit the human body) are disease triggers.
- Janus kinase (JAK) inhibitors are a newer class of drugs that, when taken orally, have proven effective in treating severe cases of alopecia areata. But hair tends to fall out again when the medication is stopped. Clinical trials are underway to test the safety and efficacy of long-term regimens of the drug, as well as topical formulations that can be directly applied to bald areas.
- Inflammation of hair follicles is a key feature of alopecia areata, and research has uncovered some of the inflammatory molecules that are likely to be involved. Clinical trials are testing the efficacy of medications called biologic response modifiers, which help to decrease or stop inflammation by targeting specific immune molecules.