Pressure Alopecia: Post-Operative Hair Loss

Pressure alopecia (also called post-operative or pressure-induced alopecia) is hair loss caused by prolonged pressure on one area of the scalp. It most often happens after a long surgery (with the head kept in one position) or after prolonged immobilization in bed. In many cases, follicles are not permanently destroyed and regrowth can occur—but severe pressure can sometimes lead to scarring.

Medical note: This article is for general education and does not provide personal medical advice. For the full roadmap, start here: Hair Loss (Complete Guide).

Pressure alopecia: localized hair loss on the back of the scalp after prolonged pressure during surgery or immobilization. — Pressure alopecia often appears on the back of the scalp (occiput) days to weeks after prolonged pressure. Early recognition matters because severe pressure can scar.

What is pressure alopecia?

Pressure alopecia is localized hair loss that develops after reduced blood flow (ischemia) to the scalp from constant pressure. The pressure typically affects scalp “pressure points,” especially the occiput (back of the head).

On our site, it belongs under: Non-Scarring Alopecia (Overview) and the main map: Types of Hair Loss. In severe cases (for example, if there was ulceration or tissue breakdown), it may behave like a scarring process—so don’t ignore pain or skin injury.

Who gets it?

People after prolonged surgery, especially when the head is fixed in one position
People who are immobilized for long periods (ICU stays, severe illness, coma)
Sometimes after tight prolonged positioning or pressure from devices/bandages

What it looks like

A well-defined patch of hair loss, often on the back of the scalp
The skin may look normal or may show tenderness, swelling, redness early on
If pressure was severe, there may be blistering, crusting, or breakdown (higher risk of scarring)

If you’re not sure whether you’re seeing shedding or breakage, start here: Shedding vs Breakage (Practical).

Timeline (when it shows up)

Pressure alopecia is often noticed days to a few weeks after the pressure event. Regrowth can happen over the following months if follicles were not permanently destroyed.

Important timing clue: If hair loss began within days to weeks after chemotherapy (rather than after pressure/positioning), see: Anagen Effluvium (Chemotherapy Hair Loss).

If shedding started 2–3 months after illness/stress/surgery (more diffuse all over), that pattern fits better with: Telogen Effluvium (Hair Shedding).

Related: if your hair loss started after surgery and you’re deciding between delayed diffuse shedding (TE) vs a localized pressure patch, read: Hair Loss After Surgery: TE vs Pressure Alopecia.

Conditions that can look similar

Localized hair loss has several common “look-alikes.” These links help you triage quickly:

Traction alopecia: more along edges/temples from tight styles → Traction Alopecia
Alopecia areata: smooth patches (often without scale) → Alopecia Areata
Tinea capitis: patchy loss with scale/broken hairs (common in kids) → Tinea Capitis
Trichotillomania: irregular patches with hairs of different lengths → Trichotillomania
Scarring alopecia red flags: shiny skin, loss of follicle openings, persistent pain/burning → Scarring Alopecia (Overview)

What to do (safe next steps)

Look for skin injury: crusting, blistering, open sores, or severe tenderness should be assessed.
Be gentle: avoid harsh chemicals and high heat while the area recovers.
Document the area: take photos weekly in the same lighting so you can track change.
Check the history: long surgery? ICU stay? prolonged positioning? This history is very helpful for diagnosis.

For a general diagnostic framework, see: How Hair Loss Is Diagnosed and Diagnosis & Care.

When to see a doctor (don’t wait)

Severe scalp pain, burning, or rapidly worsening tenderness
Blisters, pus, open sores, thick crusting, or signs of infection
Shiny smooth skin or concern for scarring
Hair loss after surgery plus fever or feeling unwell

Read: When to See a Doctor.

FAQ

Is pressure alopecia permanent?

Often it is not permanent, and regrowth may occur over months. However, severe or prolonged ischemia can lead to scarring and permanent hair loss.

How soon does it appear after surgery?

It is commonly noticed days to a few weeks after prolonged pressure/positioning. Timing varies.

How is it different from telogen effluvium?

Telogen effluvium is usually diffuse shedding that starts about 2–3 months after a trigger. Pressure alopecia is typically a localized patch linked to pressure on one scalp area.

References (trusted medical sources)

Last updated: March 1, 2026.