What alopecia is
Losing between 50 and 100 hairs a day is physiological — it's part of the follicle's natural cycle. We speak of alopecia when this loss outpaces replacement and results in a visible reduction in density, a widening parting, or bald patches.
The critical factor is the state of the follicle. While the follicle is alive, even if miniaturised, there's scope to reverse the process. Once it's replaced by fibrous tissue, the loss is permanent and only a hair transplant can restore hair to that area.
Main types of alopecia
Alopecia is essentially divided into non-scarring types, where the follicle survives, and scarring types, where it's destroyed.
- Androgenetic alopecia — the most common type; hormonal and genetic in origin, it causes progressive miniaturisation at the temples and crown
- Alopecia areata — an autoimmune condition causing round, sudden-onset bald patches
- Telogen effluvium — diffuse shedding after stress, childbirth, surgery, fever or nutritional deficiency; usually reversible
- Traction alopecia — caused by hairstyles that pull continuously on the hair
- Scarring alopecias — lichen planopilaris, folliculitis decalvans and others; require urgent treatment to halt follicular destruction
Most frequent causes
Genetic predisposition accounts for most cases, but it rarely acts alone. Hormonal changes (androgens, thyroid, post-partum, menopause), deficiencies in iron, vitamin D or protein, autoimmune disease, medication and prolonged stress are all factors that accelerate or trigger the process.
For this reason, the initial assessment often includes blood tests: treating only the scalp when the cause is systemic won't solve the problem.
How it's treated
Treatment depends on the type and stage. In early and intermediate cases, a medical approach — hair mesotherapy, PRP, topical or oral therapy and photobiomodulation — halts progression and improves density. In areas with no viable follicle left, FUE hair transplantation is the only way to restore hair.
Most cases combine both approaches: surgery to restore the lost area, and medical treatment to protect the remaining native hair.
How diagnosis is made
Diagnosing alopecia begins with clinical history: how long the shedding has lasted, whether it's diffuse or localised, family history, associated conditions, medication, or episodes of stress, childbirth or weight loss in the preceding months.
This is followed by trichoscopy — magnified examination of the scalp — which reveals signs invisible to the naked eye: hair miniaturisation, yellow or black dots typical of alopecia areata, loss of follicular openings in scarring alopecias, and signs of inflammation.
- Digital trichoscopy with standardised clinical photography
- Blood tests: full blood count, ferritin, thyroid function, vitamin D, zinc and, in women, hormone profile
- Pull test to assess the active phase of shedding
- Scalp biopsy only when scarring alopecia is suspected
Alopecia in women: what's different
In women, androgenetic alopecia rarely causes fully bald areas: it shows as a progressive widening of the central parting and diffuse thinning at the crown, while the frontal hairline is preserved. It's often mistaken for telogen effluvium, and the two conditions frequently coexist.
Periods of greater vulnerability include the post-partum period, perimenopause and menopause, as well as polycystic ovary syndrome, thyroid dysfunction or iron deficiency. This is why, in women, blood testing is almost always part of the diagnosis.
What to expect from treatment over time
Hair responds slowly because the follicle has a long cycle. In the first two to three months the goal is to halt the shedding; visible thickening appears between months 4 and 8, and the consolidated result is assessed at 12 months.
A temporary increase in shedding is common in the first few weeks of some treatments — a sign that resting follicles are being synchronised into a new growth phase, not a sign of worsening.
At Replace Clinic the plan spans an 18-month horizon, with comparable photographic reassessments rather than subjective impressions.