Alopecia Areata (AA)

This page is for you if you want to find out more about Alopecia Areata.

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An autoimmune condition that causes hair loss, most often in patches — but which can vary widely in extent.

It is best understood as a spectrum of disease, ranging from small areas of hair loss to complete loss of scalp and body hair.

 

 

 

 

What Is Alopecia Areata?

 

 

Alopecia areata is a condition in which the immune system mistakenly targets hair follicles, leading to hair loss.

 

It is a non-scarring form of alopecia, meaning:

 

• The hair follicles are not permanently destroyed

• They remain alive and capable of producing hair

 

 

This is an important point.

 

Even when hair is lost, the follicles are still present — and regrowth is often possible.

 

 

 

Hair loss in alopecia areata typically:

 

• Appears suddenly

• Affects specific areas

• Can change over time

 

 

Many people first notice:

 

• A small patch of hair loss

• Or an area that feels different when brushing or washing

 

 

 

 

 

A Spectrum of Disease

 

 

Alopecia areata is best understood as a spectrum of disease.

 

This means the same underlying condition can present in different ways and to different degrees.

 

 

 

 

Common Presentations Along the Spectrum

 

 

• Patchy alopecia areata
  Small, well-defined areas of hair loss

• Alopecia totalis
  Loss of all scalp hair

• Alopecia universalis
  Loss of scalp hair, eyebrows, eyelashes, and body hair

 

 

 

 

These are not separate diseases.

 

They represent different extents of the same underlying process.

 

 

 

Some people remain at one stage.

Others may move along the spectrum over time.

 

This variability is a defining feature of the condition.

 

 

 

 

What Is Actually Happening in Alopecia Areata?

 

 

Alopecia areata is an autoimmune condition.

 

At a biological level:

 

• Immune cells target the hair follicle

• This disrupts normal hair production

• Hair growth slows or stops

 

 

 

 

 

Loss of Immune Privilege

 

 

Hair follicles are normally protected from immune attack.

 

In alopecia areata:

 

• This protection is lost

• The follicle becomes temporarily targeted

 

 

 

 

 

Key Point

 

 

• The follicle is not destroyed

• It is functionally suppressed

 

 

This is why regrowth can occur.

 

However:

 

The timing, extent, and pattern of regrowth are not predictable.

 

 

 

 

What Does Alopecia Areata Look Like?

 

 

The most common presentation is:

 

• Well-defined round or oval patches of hair loss

• Smooth, normal-looking skin

• No scarring or scaling

 

 

 

 

 

What Patients Often Notice

 

 

• A patch that appears suddenly

• Hair loss in a specific area rather than all over

• A change that feels abrupt rather than gradual

 

 

 

 

 

Other Features

 

 

• Short “exclamation mark” hairs at the edges of patches

• Nail changes (in some individuals)

• Loss of eyebrows or eyelashes

 

 

 

 

 

How Does It Progress? (What Should You Expect?)

 

 

This is often the most important question.

 

The honest answer is:

 

Alopecia areata is unpredictable.

 

 

 

 

Patterns Seen in Practice

 

 

• Some people develop a single patch that regrows completely

• Some experience recurrent patches over time

• Some develop more extensive involvement of the scalp or body

 

 

 

 

 

Common Concerns

 

 

• “Will it spread?”

• “Will I lose all my hair?”

• “Will it grow back?”

 

 

These are entirely reasonable questions.

 

 

 

 

What We Know

 

 

• Many cases of patchy alopecia areata regrow spontaneously

• Recurrence is common

• A smaller proportion progress to more extensive forms

 

 

 

 

 

What Cannot Be Predicted Precisely

 

 

• Who will progress

• How quickly it may change

• Whether regrowth will be complete

 

 

This uncertainty is part of the condition, and can be one of the most difficult aspects to manage.

 

 

 

 

If You Notice Sudden Patchy Hair Loss — What Should You Do?

 

 

If you develop sudden, localised hair loss, it is reasonable to seek assessment.

 

This allows:

 

• Confirmation of diagnosis

• Assessment of extent and activity

• Discussion of appropriate options

 

 

It also helps to:

 

• exclude other causes

• and set realistic expectations

 

 

 

 

 

How Is Alopecia Areata Diagnosed?

 

 

Diagnosis is usually clinical.

 

 

 

 

Clinical Examination

 

 

• Smooth, well-defined patches

• No scarring

 

 

 

 

 

Trichoscopy

 

 

Typical findings:

 

• Exclamation mark hairs

• Yellow dots

• Black dots

 

 

 

 

 

Additional Assessment

 

 

• Hair pull test

• Blood tests (if indicated)

 

 

 

 

 

The Emotional Impact — and Why It Matters

 

 

Alopecia areata often affects visible areas and can change quickly.

 

For many people, this can feel:

 

• Sudden

• Uncertain

• Difficult to explain

 

 

One of the most challenging aspects is:

 

Not knowing how it will behave over time

 

This uncertainty can be as significant as the hair loss itself.

 

These responses are understandable.

 

Clear information, realistic expectations, and appropriate support can help people navigate this period.

 

 

 

 

Which Treatments for Alopecia Areata Actually Work?

 

 

Treatment aims to:

 

• Modify the immune response

• Encourage regrowth where possible

 

 

 

 

 

Corticosteroids

 

 

• Topical or injected

• Often first-line for patchy disease

 

 

 

 

 

Systemic Treatments

 

 

• Used in more extensive cases

• Include immunomodulatory therapies

 

 

 

 

 

JAK Inhibitors

 

 

• Target immune pathways

• Increasing evidence for moderate to severe disease

 

 

 

 

 

Minoxidil (Adjunctive)

 

 

• May support regrowth

• Typically used alongside other treatments

 

 

 

 

 

A Realistic Perspective

 

 

• Some patients regrow without treatment

• Some respond well to treatment

• Some experience recurrence or progression

 

 

 

 

 

Key Point

 

 

Alopecia areata is:

 

• Autoimmune

• Non-scarring

• A spectrum of disease

• Unpredictable

 

 

If there is one takeaway:

 

Hair follicles remain intact, and regrowth is often possible — but the course varies from person to person.

 

 

 

 

In Summary

 

 

Alopecia areata is an autoimmune condition that causes hair loss, most often in patches but sometimes more extensively.

It exists on a spectrum from small areas of loss to complete loss of scalp and body hair.

The follicles are not permanently damaged, meaning regrowth is possible — but the condition is often unpredictable.

 

 

 

 

Frequently Asked Questions

 

 

Is alopecia areata one condition or several?

It is one condition with a range of presentations (a spectrum).

 

 

 

Will my hair grow back?

Often, yes — but timing and extent vary.

 

 

 

Can it spread?

It can, but not always.

 

 

 

Can it progress to total hair loss?

It can, but this is less common.

 

 

 

Is it permanent?

Usually not, but recurrence is common.

 

 

 

 

Authored by: Dr Gwen Adey BDS MFDS RCS

Date first published:

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