When to see a dermatologist

Most gradual hair thinning is pattern loss and can be started on over-the-counter treatment (see the treatment ladder). Some presentations should skip the shelf and go to a clinician quickly, because delay can cost permanent hair or miss a medical problem. This page lists those red flags with the evidence behind each. It is a triage aid, not a diagnosis.

Key takeaways

• Scarring (cicatricial) alopecias destroy follicles permanently, so earlier treatment preserves more hair. The European task force stresses early diagnosis in lichen planopilaris (Seyed Jafari 2026).
• Symptoms on the scalp are the biggest red flag: pain, burning, tenderness, stinging, itching with scale or crust, tiny bumps, or a smooth shiny patch (Seyed Jafari 2026).
• A hairline that recedes with thinned eyebrows, or beard loss in men, is not normal ageing: think frontal fibrosing alopecia (Melian-Olivera 2025).
• In curly or coily hair, centre-crown breakage can be the first sign of CCCA, and diagnosis is often late (Issa 2026). Misdiagnosis of scalp conditions in skin of colour is documented (McMullen 2026); ask directly about a biopsy if first-line treatment fails.
• Scaly bald patches in a child are tinea capitis until proven otherwise. They need an oral antifungal and a lab test, and shampoo will not cure them (Mayser 2026).
• Hair loss can be the visible edge of a systemic problem such as thyroid disease, iron deficiency, androgen excess like PCOS, or a medicine. In women with pattern loss, an expert report recommends assessing for androgen excess and suggests checking vitamin D, iron, zinc, thyroid hormones and prolactin (Carmina 2019).
• Compulsive hair pulling responds to behavioural therapy and benefits from specialist input (Fisak 2026).

Red flag checklist

What a dermatologist does

They examine the hairline, scalp and eyebrows, ask about symptoms and medicines, may use a dermatoscope (Pirmez 2023), and often take a small scalp biopsy under local anaesthetic to confirm the type. Pull tests and blood tests complete the work-up. Biopsy and prescribing need a doctor.

In lymphocytic scarring alopecias such as lichen planopilaris and frontal fibrosing alopecia, immune cells attack the follicle and the loss is irreversible, so the treatment aim is stabilization. Dutasteride, steroids and hydroxychloroquine are used off-label for frontal fibrosing alopecia, and randomized evidence is very limited (Saceda-Corralo 2026).

Delays are common. Older adults with tinea capitis were misdiagnosed in 37.4% of reported cases (Valdez-Martinez 2025).

Hair type notes

• Curl 3A to 4C and protective styles: check the crown and edges with a mirror monthly, because styles can hide both traction and CCCA. Ask for a clinician experienced in textured hair, and for a biopsy if the first diagnosis of dryness or dandruff does not respond.
• Straight or fine hair: thinning shows earlier at the part, and pattern loss is likelier.
• Oily or flaky scalp: persistent flaking with hair loss that does not improve after a few weeks of medicated shampoo is a reason to check for tinea or inflammatory disease (see sebum and scalp types).
• Children: see within days for scaly patches, and prevent tight braids on young girls (see traction and hairstyles).
• Men with an early receding hairline can start proven treatments, but a hairline with brow loss still needs a check. Women with irregular periods or excess facial hair need a hormone assessment.

Myths and facts

• "Wait six months and see" is fine for mild gradual shedding, not for scarring signs.
• A trichologist cannot biopsy or prescribe; that needs a doctor.
• If it does not hurt it is not necessarily harmless: many scarring alopecias are silent.
• Photographs help. Bring dated photos, a medication list and family history.

Bottom line

Take photos now of the hairline, part, crown and brows in the same light, and repeat monthly. Write down onset, symptoms, new products, styles, illnesses, medicines, family history and periods. Book a board-certified dermatologist, or in the UK your GP and then a dermatology referral; private teledermatology can triage but cannot biopsy. Request bloods only when guided by history, and do not self-supplement iron without a result (see iron and ferritin). Do not start new potent products on an inflamed or painful scalp before diagnosis. Once pattern loss is confirmed, see the treatment ladder. Discuss with a doctor.