Alopecia

Alopecia is simply the medical word for hair loss, of any kind, anywhere on the body. It is less a single disease than a category — a label that sits above a whole family of very different conditions, some trivial and reversible, some permanent.^{[citation needed]}

A word borrowed from the fox

The term goes back to the ancient Greeks — Hippocrates used it — and it comes from alōpēx, the Greek for “fox.” The usual explanation is “fox-sickness”: foxes are prone to mange and molt their coats, so a patchily balding human was said to have the fox’s affliction. Centuries of medicine, and we are still naming baldness after a shedding woodland animal.¹

The main kinds

• Androgenetic alopecia — ordinary male- and female-pattern baldness, and by far the most common type.² It is driven by genetics and by follicle sensitivity to a hormone called DHT (dihydrotestosterone), which gradually shrinks affected follicles until they produce only fine, barely-there hair. This is the baldness behind the entire war against baldness, from the comb-over to the toupée.
• Alopecia areata — an autoimmune condition that attacks follicles and produces sudden, smooth, round bald patches. It gets its own article.
• Telogen effluvium — a temporary, diffuse shedding that follows a shock to the system (illness, surgery, childbirth, crash diet, major stress). It pushes many follicles into their resting phase at once, so the hair falls out together a couple of months later. It almost always grows back.
• Traction alopecia — hair loss from chronic pulling: tight ponytails, braids, and buns slowly tugging hair out at the hairline.
• Scarring (cicatricial) alopecia — a group of conditions in which the follicle is destroyed and replaced by scar tissue. Unlike the others, this one is usually permanent, because there is no follicle left to recover.

The treatments (and a happy accident)

The two best-known drugs for pattern baldness arrived by very different routes. Finasteride was designed to block the enzyme that makes DHT. Minoxidil, by contrast, started life as an oral drug for high blood pressure — until doctors noticed patients growing hair in unexpected places, and the side effect became the product. Much of modern hair-loss medicine is, in other words, a repurposed blood-pressure pill and a hormone blocker.^{[citation needed]}

See also

• Alopecia areata
• The comb-over and the toupée
• Why hair turns gray
• Keratin

References

1. “alopecia.” Online Etymology Dictionary. etymonline.com. (From Greek alōpēx, “fox.”) ↩

2. “Androgenetic Alopecia.” In: StatPearls [Internet]. StatPearls Publishing (NCBI Bookshelf NBK430924). ↩