Hair loss diagnosis at a Seoul clinic

1. History: when the loss started, how fast, and what changed in the months before.
2. Examination of the scalp, hairline, eyebrows and nails, and a gentle pull test.
3. Trichoscopy: magnified images of the scalp and hair shafts.
4. Standard photos of the top, front and crown, taken the same way at each visit.
5. Blood tests, if your history or the examination suggests a cause they can find.
6. A diagnosis and a written plan: what to start now and when to review progress.

• Did it start suddenly or slowly? Is it shedding, thinning or bald patches?
• Any high fever, surgery, childbirth, rapid weight loss or major stress in the last three to six months?
• Which medicines and supplements do you take, and since when?
• Does anyone in your family have pattern hair loss?
• For women: regular periods, acne, extra facial hair, pregnancy plans.
• Hair care: colouring, bleaching, perms, tight hairstyles, extensions.
• Previous hair loss treatments, how long you used them and what changed.

Two things make the visit faster: old photos that show your hair a few years ago, and a list of your medicines with their generic names, which translate more reliably than brand names.

Trichoscopy is an examination with a handheld dermoscope or a video dermoscope. A review of the method describes it as an essential tool for telling hair and scalp diseases apart^[1]. It takes a few minutes, causes no discomfort, and the images become your baseline for later comparison.

The pattern-hair-loss, alopecia areata and scarring findings above come from the trichoscopy review^[1]. The Asian consensus guideline adds a way of recording pattern hair loss, the BASP classification, that suits patterns more common in Asian patients^[2].

The doctor holds a small bundle of hairs between the fingers and slides along them with a light pull. If several hairs come out easily, shedding is active. The test is repeated in different areas, so tell the doctor if you washed your hair that morning, because washing removes hairs that were ready to fall.

Not everyone needs blood tests. They are useful when the history suggests a cause they can detect. Tests often include iron stores (ferritin), a full blood count and thyroid function, and hormone tests for women with irregular periods, acne or extra facial hair.

Iron is especially relevant for women. In a study at Seoul National University, women with pattern hair loss had lower average ferritin than healthy women (49 versus 78 µg/L), and 22.7% of men with pattern hair loss had ferritin below 70 µg/L, compared with none of the healthy men^[3]. Ask when results will be ready. If you leave Seoul before then, ask for them by email, in English, with the reference ranges.

A biopsy is considered when trichoscopy suggests scarring alopecia, when the pattern does not fit a clear diagnosis, or when treatment is not working as expected. It is a small procedure under local anaesthetic. Laboratory results take longer than a short stay, so agree how you will receive them and who will explain them.

Hair grows slowly, so the first visit sets the baseline. Trials of finasteride and dutasteride measured results after 24 weeks to two years^[4][5]. Photos and trichoscopy images from the same spots, in the same light, are what make a later comparison meaningful.