Androgenetic Alopecia
Androgenetic alopecia is the clinical name for male and female pattern hair loss: the gradual, genetically determined shrinking of scalp follicles under the influence of [DHT](/glossary/dht).
Where you'll meet it
On every consultation note and every prescription. It is the diagnosis behind more than nine in ten cases of hair loss in men, and a large share in women.
What it actually is
Susceptible follicles respond to DHT by miniaturising, producing progressively finer, shorter, lighter hairs over successive cycles until they stop producing visible hair at all. It is not hair falling out so much as hair becoming imperceptible.
Which follicles are susceptible is set genetically, and the pattern it follows is described by the Norwood scale. The horseshoe at the back and sides is generally not susceptible, which is the entire basis of transplant surgery.
Why the distinction matters
Other kinds of loss look different and are treated differently. Telogen effluvium is diffuse shedding after a stressor and usually recovers. Alopecia areata is patchy and autoimmune. Scarring alopecias destroy the follicle permanently and need a dermatologist urgently.
Finasteride and minoxidil are treatments for androgenetic loss. Using them on something else wastes time that a correct diagnosis would have saved.
Related pages
Thinking about a transplant?
The Start Here guide explains why medical treatment comes first, how much donor hair you actually have, and what a transplant can and cannot move.
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