Alopecia areata
- What it is
- Autoimmune — the follicle is attacked, not destroyed
- Follicles
- Remain alive, so regrowth is possible even years later
- Single patches
- Often regrow on their own within a year
Alopecia areata causes sudden, well-defined round or oval patches of hair loss, most often on the scalp but possible in the beard, eyebrows, eyelashes or anywhere else hair grows. The skin in the patch looks normal — not scaly, not scarred, not inflamed.
It is autoimmune. The immune system attacks the hair follicle and switches it off. Crucially, it does not destroy it, which is why regrowth remains possible even in patches that have been present for a long time.
How much it affects
- Patchy alopecia areata — one or several discrete patches. The common form, and the one most likely to regrow spontaneously
- Alopecia totalis — loss of all scalp hair
- Alopecia universalis — loss of all body hair
- Ophiasis pattern — a band along the lower back and sides of the scalp; tends to respond less readily
How it is assessed
Trichoscopy is the key examination. It shows the characteristic features — exclamation-mark hairs, yellow dots, black dots — and confirms that follicle openings are preserved, which distinguishes this from scarring alopecia where they are lost. That distinction determines whether regrowth is possible at all.
A KOH mount or fungal culture is worth doing in children, where tinea capitis is the main alternative. Because it is autoimmune, thyroid function is checked, and other autoimmune conditions are asked about. Nails are examined — fine pitting is common and supports the diagnosis.
Treatment
Limited patches
Intralesional steroid injections into the patch are the standard and most effective approach, repeated every four to six weeks. Potent topical steroids and topical minoxidil are used alongside, particularly in children where injections are not appropriate.
More extensive disease
Topical immunotherapy, oral immunosuppressants, or JAK inhibitors depending on severity, duration and what has already been tried. Each needs screening and monitoring.
Where watchful waiting is reasonable
A single small patch in an otherwise well person often regrows by itself. Choosing to observe for a few months, with a review date, is a legitimate plan rather than a failure to treat — and it will be offered as an option rather than treatment being pushed.
The part that is usually left out
Sudden visible hair loss is distressing out of proportion to its medical seriousness, and that is worth saying rather than brushing past. The condition causes no physical harm and no illness. That does not make the experience of it trivial, and the consultation should have room for both facts.
What else it could be
These are the conditions this is most often mistaken for. Treating the wrong one is the commonest reason a problem drags on for months.
| Often mistaken for | How it's told apart |
|---|---|
| Tinea capitis | Fungal scalp infection, mostly in children — scaly, broken hairs and sometimes boggy swelling. Needs oral antifungals, not steroids. |
| Trichotillomania | Hair pulling, producing irregular patches with hairs of varying length rather than a smooth bald patch. |
| Traction alopecia | Follows tension from hairstyles, and recedes along the hairline rather than appearing as discrete round patches. |
| Scarring alopecia | The scalp surface looks smooth and shiny with no visible follicle openings — in alopecia areata the openings are preserved. |
| Secondary syphilis | Can cause a moth-eaten pattern of patchy hair loss. Uncommon, easily tested, and worth remembering. |
Common questions
Will my hair grow back?
In most people with a single patch or a few small patches, yes — often within six to twelve months, sometimes without any treatment. The follicles are not destroyed, only switched off, which is why regrowth remains possible even after a long period. More extensive disease is less predictable.
Was this caused by stress?
Stress may act as a trigger in some people, but it is not the cause. Alopecia areata is autoimmune — the immune system attacks the hair follicle. Being told it is "just stress" is a common experience and it is not an adequate explanation.
Will it come back after it regrows?
It can. The course is unpredictable, with periods of regrowth and occasional recurrence. Knowing this in advance makes a recurrence much less distressing than discovering it unexpectedly.
Is the new white hair permanent?
Usually not. Regrowth often comes back fine and white or grey at first, and pigment typically returns over the following months.
What about the newer tablets I have read about?
JAK inhibitors have changed treatment for severe and extensive alopecia areata, with substantial regrowth in many patients. They require screening before starting, ongoing monitoring, and continued use to maintain the effect. They are appropriate for severe disease, not for a single small patch.
This page is general information and does not replace a consultation. Whether any treatment described here is right for you depends on examination, history and other medicines, and that assessment needs a doctor.