What Is Androgenetic Alopecia? A Plain-English Guide to Pattern Hair Loss

If you've started Googling what's happening to your hair, you've probably seen the term androgenetic alopecia. It sounds clinical and a little intimidating, but it just describes the most common type of hair loss in adults, the one that runs in families and shows up as a receding hairline, a thinning crown, or a widening part. By midlife, roughly half of men and a substantial share of women will have some degree of it.

Here is what androgenetic alopecia actually is, why it happens, and what's known to slow or partly reverse it.

Breaking down the name

The term itself tells you most of what you need to know.

• Andro- points to androgens, the family of hormones that includes testosterone and its more potent cousin, dihydrotestosterone (DHT).
• -genetic points to inheritance. Susceptibility runs in families and is passed down from both parents.
• Alopecia is the umbrella medical word for hair loss of any kind.

Put together, androgenetic alopecia is a hereditary form of hair loss that depends on how scalp follicles respond to androgens. It is also called pattern hair loss, male pattern baldness, or female pattern hair loss, depending on who has it and how it presents.

How common is it?

Androgenetic alopecia is the most common cause of hair loss worldwide. According to a frequently cited review in the Journal of the American Academy of Dermatology, roughly 50% of men show clinically meaningful pattern hair loss by age 50, and prevalence keeps climbing with age. In women, an estimated 40% experience visible thinning by age 70, with most cases beginning in their 40s or 50s. Onset in the late teens or twenties is not unusual, particularly in people with strong family histories on either side.

That prevalence is part of why the condition is sometimes dismissed as cosmetic. It is genuinely common, but it is still a progressive medical condition with real treatment options, and it tends to respond better to early intervention than late intervention.

The mechanism, in plain language

Androgenetic alopecia is not caused by clogged pores, poor circulation, stress, hats, or shampoo. It comes from a specific interaction between two things: inherited follicle sensitivity, and a hormone called DHT.

Here is the chain of events:

1. The enzyme 5-alpha reductase converts a small portion of circulating testosterone into DHT, a more potent androgen.
2. DHT binds to receptors on the hair follicles at the top and front of the scalp. (Follicles at the sides and back of the head do not have the same sensitivity, which is why those areas usually keep their hair.)
3. Each cycle of binding shortens the active growth phase, called anagen, and shrinks the follicle a little. We cover that growth cycle in more depth in how the hair growth cycle works.
4. Over many cycles, the once-terminal hairs become shorter, thinner, and less pigmented. Eventually, the follicle produces only a wispy "vellus" hair, and finally goes dormant.

This stepwise shrinking is called follicle miniaturization, and it is the cellular signature of androgenetic alopecia. For a deeper look at the hormonal driver, see our guide on what DHT is and why it causes pattern hair loss.

One myth worth correcting: androgenetic alopecia is not a sign of high testosterone. Most people with pattern hair loss have completely normal hormone levels. The issue is how their follicles respond to DHT, not how much DHT they make.

How it tends to show up

The pattern is different between men and women.

In men, the classic progression is a receding hairline at the temples, sometimes called an M-shape, and gradual thinning at the crown. Over years, those two areas can merge and leave the familiar horseshoe of retained hair around the sides and back. Dermatologists describe this progression using the Norwood-Hamilton scale, which ranges from stage I (a youthful hairline) to stage VII (extensive loss).

In women, the pattern is usually a diffuse thinning across the top of the scalp, most visible along the central part, with the frontal hairline generally preserved. The Ludwig scale grades it in three stages, from mild widening of the part to extensive central thinning. Frank baldness is rare in women with androgenetic alopecia.

In both cases the back and sides of the scalp usually keep their density because those follicles are not sensitive to DHT. That is also why hair transplantation works the way it does: hairs are relocated from the resistant zone to areas that have thinned.

How it's different from other types of hair loss

A few conditions are commonly confused with pattern hair loss because they can produce visible thinning, but they have different causes and different treatments.

• Telogen effluvium is a temporary shedding response to a stressor: childbirth, surgery, a serious illness, rapid weight loss, or a new medication. It usually resolves on its own within 3 to 6 months once the trigger has passed.
• Alopecia areata is an autoimmune condition that causes well-defined patchy hair loss, often in coin-sized circles. It is not hormonal and responds to immune-targeted treatments rather than DHT-blockers.
• Traction alopecia comes from chronic mechanical tension on the hair, often from tight hairstyles. It can become permanent if the underlying tension is not removed.
• Scarring alopecias are a smaller group of conditions where inflammation destroys the follicle. These need specialist evaluation because they behave very differently from pattern loss.

A clinician can usually distinguish androgenetic alopecia from these by history and visual examination, sometimes supplemented by a pull test, trichoscopy, or routine blood work to rule out things like thyroid issues or iron deficiency.

What actually treats it

Several treatments have solid clinical evidence for slowing, halting, or partially reversing androgenetic alopecia. None cure it, and results depend on continued use. The most-studied options:

• Minoxidil, available as a topical solution or low-dose oral pill. It extends the growth phase and enlarges miniaturized follicles. It does not block DHT, so it is often paired with a DHT-targeted medication. See our explainer on how minoxidil treats hair loss for the full picture.
• Finasteride, an oral medication that blocks 5-alpha reductase and reduces scalp DHT by roughly 60 to 70%. It addresses the hormonal driver directly. Our guide how finasteride treats hair loss walks through the evidence.
• Dutasteride, a more potent 5-alpha reductase inhibitor used off-label in some cases for stronger DHT suppression.
• Spironolactone, an anti-androgen used in some women with pattern hair loss, particularly those with elevated androgen markers. Not appropriate during pregnancy.
• Combination therapy, typically minoxidil plus finasteride, which produces better outcomes than either alone for many patients.

Approaches with weak or no evidence (biotin in the absence of deficiency, caffeine shampoos, saw palmetto, scalp massage devices) tend to absorb a lot of time and money without changing the underlying trajectory. The FDA-approved medications above are still the most reliable starting point.

Why early matters

Follicles affected by androgenetic alopecia can recover when treatment is started in the early stages of miniaturization. Follicles that have been fully dormant for years are much less likely to wake up. That is the practical case for not waiting: the same medication started at stage II of Norwood usually does more visible work than the same medication started at stage V.

The bottom line

Androgenetic alopecia is common, hereditary, hormonally driven, and treatable. It is not your fault, it is not caused by anything in your shampoo, and it is not a fixed sentence. A licensed physician can confirm the diagnosis, rule out other causes, and recommend an evidence-based plan that fits your stage and medical history. That is the kind of care Curekey is built to provide.

Knowing the name of what is happening is a good first step. The next one is a conversation with someone who can help you decide what to do about it.