Synopsis
Recognise immune-mediated non-scarring hair loss, exclude infection and follicular destruction, grade extent and impact, and use topical or systemic treatment with realistic relapse and safety counselling.
- Alopecia areata causes sharply defined smooth patches of non-scarring hair loss; follicular openings remain visible and the scalp is usually neither markedly inflamed nor scaly.
- Exclamation-mark hairs, black dots, broken hairs, yellow dots and short tapered regrowth support active disease but no single dermoscopic feature is mandatory.
- Examine eyebrows, eyelashes, beard, body hair and nails; pitting or rough trachyonychia supports the diagnosis and extensive loss changes prognosis and treatment eligibility.
- Tinea capitis produces scale, broken hairs or lymphadenopathy and needs fungal sampling and systemic antifungal care; a boggy kerion risks permanent scarring.
- Thyroid and other autoimmune disease are associated, but blood testing should follow symptoms, personal history, family history or clinical indication rather than a universal broad panel.
- Limited patches may regrow spontaneously. Potent topical corticosteroid or intralesional corticosteroid can be discussed, with site, age, pain and skin-atrophy risks considered.
- NICE recommends baricitinib for severe alopecia areata in eligible adults and ritlecitinib for severe disease from age 12, delivered through specialist pathways with infection and reproductive safeguards.
- Relapse can follow any treatment, and regrowing hair may initially be fine or white. Address camouflage, wigs, brows, lashes and psychological impact alongside biological therapy.
Key red flags
Loss of follicular openings, scalp pain, perifollicular scale, pustules, boggy inflammation, a rapidly enlarging mass or systemic illness is not uncomplicated alopecia areata and requires urgent infection, scarring-alopecia or tumour assessment.
Absent openings, perifollicular erythema or scale, pustules, pain and shiny atrophy point away from alopecia areata toward scarring disease.
Investigation priorities
Confirm non-scarring loss and measure anatomic extent beyond the reported patch.
Management branches
One or a few smooth patches are present without infection or scarring features.
- Examine scalp, brows, lashes, body hair and nails, use trichoscopy where available and sample fungus only when scale or exposure supports it.
- Explain spontaneous regrowth, variable recurrence and prognostic factors, then offer observation, camouflage or a defined topical corticosteroid course according to age, site and preference.
- Photograph with consent and review after a hair-cycle interval, referring progression, diagnostic uncertainty or substantial distress rather than simply enlarging topical quantities.
Key medicines
Potent topical corticosteroid for limited scalp diseaseApply the prescribed scalp formulation thinly once daily for a defined course, commonly reviewed after six to twelve weeks before any continuation or break.Avoid prolonged uncontrolled use, especially on face or brows; monitor atrophy, telangiectasia and folliculitis, and account for total area, occlusion and concurrent corticosteroids.
BaricitinibEligible adults take the specialist-selected oral dose once daily, usually 4 mg or 2 mg when age, risk, interactions or tolerability favour the lower dose.Screen for tuberculosis and viral hepatitis, update appropriate vaccination and monitor blood counts, liver tests and lipids. Review serious infection, herpes zoster, thrombosis, cardiovascular and malignancy risks, especially in older smokers; avoid pregnancy.