Thank you for describing everything so clearly, and thank you for the details and the photograph (not shown for privacy). Your story strongly aligns with alopecia areata, which typically presents as sudden, smooth, round patches of hair loss due to the immune system targeting hair follicles. Mimickers include tinea capitis, which usually shows scaling or broken-off hairs; telogen effluvium, which causes diffuse shedding rather than circular patches; and traction alopecia, which often develops from hairstyles causing repeated pulling. The sudden, sharply defined, smooth patches you described are most consistent with alopecia areata.

How urgently this needs to be managed

This is generally semi-urgent because sudden hair loss can be distressing and early evaluation helps guide management. A dermatology review within 1–2 weeks is reasonable, especially if new patches continue appearing.

Seek urgent care if these occur

Seek earlier attention if you notice:

• Rapid expansion of patches within days

• Pain, redness, or scaling suggesting another cause

• Loss of eyelashes or eyebrows

• Hair loss accompanied by fatigue, fever, or other systemic symptoms

The following self-care and over-the-counter measures may sometimes help

I know how emotionally difficult sudden hair loss can be. Gentle care helps protect the remaining hair—avoid tight hairstyles, heat styling, and harsh chemical treatments. Keeping the scalp clean and avoiding excessive brushing may also reduce mechanical stress.
You may also consider:

• Using mild, fragrance-free shampoos

• Avoiding vigorous scalp massage

• Managing stress where possible, as it can sometimes trigger flares

What dermatologists commonly prescribe

Dermatologists may use topical or targeted anti-inflammatory treatments, scalp-directed procedures, or systemic therapies depending on how extensive the patches are.
The exact choice of treatment depends on a full in-person evaluation and individual medical factors.
When diagnosis is uncertain, dermoscopy or a small scalp biopsy may help differentiate similar conditions.

If the condition does not improve

If patches continue to form or existing ones enlarge, a follow-up dermatology visit is usually the next step to adjust the approach and confirm the underlying cause.

Before you go

Sudden hair loss is understandably upsetting, but many people experience significant regrowth with the right care. I’m here if you’d like to share photos or talk through next steps.

Disclaimer

This is an anonymised educational example only. It is not medical advice and should not replace consultation with a qualified dermatologist.