Conditions · Hair · Pattern Loss

Androgenetic Alopecia (Pattern Hair Loss)

Androgenetic alopecia is the diagnosis behind most thinning heads: genetically sensitive follicles responding to normal androgen levels by miniaturising — each growth cycle producing a finer, shorter, paler hair than the last, until the follicle retires. It runs on a timetable written in your genes, it is progressive by default, and it is the best-evidenced treatable form of hair loss in medicine.

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Key Facts

The mechanism
Dihydrotestosterone (DHT) acting on genetically sensitive follicles → progressive miniaturisation
The male pattern
Norwood stages: temples and crown first, the classic M-shape and vertex thinning
The female pattern
Ludwig stages: diffuse widening of the central parting with a preserved frontal hairline
The key insight
Hormone levels are usually normal — sensitivity, not excess, drives the loss
Guideline treatments
Topical minoxidil and (in men) oral finasteride anchor the evidence-based S3 guideline ladder
The timing truth
Every treatment defends and thickens surviving follicles best — miniaturisation is reversible, bare scalp largely is not

How pattern loss actually happens

Follicles in the pattern zones — temples and crown in men, the central scalp in women — carry inherited sensitivity to dihydrotestosterone. Under DHT's influence each hair cycle shortens and each regrown hair miniaturises: finer calibre, shorter length, less pigment, until terminal hairs have become barely-visible vellus fuzz and, eventually, the follicle falls dormant [1]. Two clarifications the internet muddles: hormone levels are usually normal — sensitivity is the inheritance, which is why blood tests are often unremarkable — and the pattern's shape is the diagnosis's signature, distinct in men (receding temples and crown) and women (a widening parting behind an intact hairline).

Pattern loss or something else?

The pattern and the timeline separate AGA from its neighbours. Gradual thinning in the classic zones over years is AGA. Diffuse shedding in handfuls after illness, childbirth or crash dieting is telogen effluvium — a different, usually self-limiting process. Coin-shaped bare patches with sharp edges are alopecia areata, an autoimmune event. A receding edge tracking years of tight hairstyles is traction. And a flaky, inflamed scalp thins hair by its own route — see seborrhoeic dermatitis. The conditions coexist happily, and a shedding episode often unmasks underlying AGA — which is why diagnosis precedes every plan here.

What actually works

AGA holds the strongest treatment evidence in hair medicine, codified in the European S3 guideline [1]: topical minoxidil for men and women, oral finasteride for men — both slowing loss and partially reversing miniaturisation in trial after trial — with the guideline framing treatment as long-term, since benefit persists only while treatment continues. Around that pharmacological spine, Dr Sin Yong's programmes layer the clinic arm: medication management, H2LT laser hyperstimulation, Regenera Activa micrograft therapy, and the assessment-led pathways of the male and female hair loss programmes — with restoration planning for advanced zones. The single most consequential variable is the calendar: treatment defends follicles that still exist. Miniaturised is recoverable; bare and shiny mostly is not.

What doesn't work

Waiting a few more years 'to see how bad it gets' — the answer arrives with fewer follicles to save. Caffeine shampoos and biotin as a strategy — supermarket adjuncts against a hormonal mechanism. Scalp massage rituals — circulation was never the problem. Stopping effective treatment once things improve — AGA resumes its timetable within months of the last dose. And for women, assuming nothing can be done because finasteride headlines are male — the female pathway has its own evidence-backed ladder, which is what the assessment maps.

“Pattern hair loss treatment defends the hairs you still have — which is why the best year to start is always the year you first wondered.”

— Dr Sin Yong

Questions Patients Actually Ask

Is androgenetic alopecia only a male condition?+

No — female pattern hair loss is the same follicular biology in a different distribution: a widening parting rather than receding temples. It affects a large share of women, rising after menopause.

My hormones tested normal — how can it be hormonal?+

Because the mechanism is follicle sensitivity to normal DHT levels, not hormonal excess. Normal blood work is the typical AGA finding, not evidence against it.

Does minoxidil work?+

It carries guideline-level evidence in men and women — slowing loss and thickening miniaturised hairs — with effect maintained only during continued use, and an early temporary shed as cycles resynchronise.

Is finasteride safe?+

It is a prescription medicine with a defined, extensively studied profile in men — the risk-benefit conversation is individual and belongs with a physician, which is exactly how it is prescribed here. It is not used in women of childbearing potential.

Can lost hair come back?+

Miniaturised, still-cycling follicles can recover calibre with treatment. Zones bare and shiny for years hold few salvageable follicles — the honest boundary between medical treatment and restoration planning.

How fast does treatment show results?+

Hair answers in cycles, not weeks: expect several months before change is visible and about a year for a fair verdict — with photographs, not memory, keeping score.

References

  1. Evidence-Based (S3) Guideline for the Treatment of Androgenetic Alopecia in Women and in Men — Journal of the German Society of Dermatology (PubMed).
  2. Androgenetic Alopecia (Male and Female Pattern Hair Loss) — DermNet NZ.
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