Folliculitis decalvans: scarring scalp inflammation that causes hair loss

Folliculitis decalvans is an uncommon cause of hair loss that scarring specialists want people to recognise early. It is a chronic inflammation of hair follicles that can permanently destroy follicles if not brought under control, according to the British Association of Dermatologists (BAD) and ubiehealth.com.

This condition mainly affects the scalp but can involve other hair‑bearing skin. It is estimated to affect between 1 in 10,000 and 1 in 25,000 people, with men more commonly affected than women, and most cases presenting in adulthood, BAD reports.

What happened

Dermatology guidance describes folliculitis decalvans as a long‑term follicle‑centred inflammation that often leads to scarring hair loss. The scalp may show redness, swelling, scabs and crusts, with tender or itchy areas that can bleed or ooze. Shiny skin in bald areas reflects follicle loss and permanent alopecia.

A distinctive clinical clue is “tufting”, where multiple hairs emerge from a single enlarged follicle opening, creating a bristle‑like look. Any scalp region can be affected, and the condition may heal then flare again over months or years.

The exact cause is unknown, but BAD notes a suspected abnormal immune response to Staphylococcus aureus, a bacterium that commonly lives on skin. The disorder itself is not passed between people, though S. aureus can be contagious.

Diagnosing folliculitis decalvans relies on a careful scalp examination, often with a dermatoscope to inspect follicle openings. Doctors may take swabs, scrapings or plucked hairs to look for bacteria or fungi, because ringworm and other infections can look similar on first inspection.

Where uncertainty remains, a small scalp biopsy may be recommended to confirm scarring inflammation and rule out other cicatricial (scarring) alopecias. Local anaesthetic is used for the procedure, and a small scar may result after stitches are removed.

There is currently no cure. Treatment focuses on reducing inflammation, slowing spread and preventing further scarring. Because the condition is rare, there are no robust head‑to‑head trials showing one option is best, and plans are individualised by specialists.

Therapies used include medicated shampoos, antibacterial or anti‑inflammatory scalp solutions and topical corticosteroids. Oral antibiotics such as tetracyclines are commonly prescribed, with combinations like clindamycin and rifampicin used in some cases when bacterial involvement is suspected.

For more severe or relapsing disease, dermatologists may consider steroid injections into active areas, short courses of oral steroids during flares, or tablets such as isotretinoin, acitretin, hydroxychloroquine, dapsone or ciclosporin. Immune‑targeting medicines including adalimumab, infliximab, tofacitinib and baricitinib have been used in selected cases, alongside photodynamic therapy, but evidence remains limited.

Cosmetic options can help conceal hair loss while medical care continues. BAD notes NHS support for wigs and hairpieces via prescription vouchers, with patient contributions varying. People also use hair‑building fibres or pursue private scalp micropigmentation.

Hair transplantation is a surgical option only once the condition has been inactive for many years without treatment, due to the risk of renewed inflammation damaging transplanted follicles. Our guide to hair transplant recovery: risks and when to seek help explains key considerations and red flags after surgery.

The background

Folliculitis means inflammation of a hair follicle. Scalp folliculitis is relatively common and may be triggered by bacteria, yeasts, viruses or mechanical irritation, ubiehealth.com explains. Most mild folliculitis settles and hair regrows, but chronic deep forms such as folliculitis decalvans can scar, leading to permanent hair loss.

Symptoms vary. Some people report itch, tenderness or a tight feeling in the affected area, while others notice no discomfort. Yellow pus‑filled spots, crusts and scabs can appear around follicles, with soreness if pustules enlarge or combine. Tufted hairs and shiny scalp in bald patches are hallmarks of scarring disease.

Although classically a scalp disease, folliculitis decalvans can also affect the beard area and body sites with hair. BAD emphasises it is not a type of skin cancer, which can reassure people alarmed by persistent sores or bleeding.

Ubiehealth.com lists factors that can drive or worsen scalp folliculitis more broadly: bacterial overgrowth (often S. aureus), Malassezia yeast, exposure to wet environments, tight hairstyles, scratching and harsh chemical treatments. Heavy, occlusive styling products and sweat can add to the problem, and underlying conditions such as diabetes or a weakened immune system may raise risk.

In women, scalp folliculitis can overlap with other causes of thinning, including female pattern hair loss, seborrhoeic dermatitis and lichen planopilaris. Correct diagnosis is important because timing and treatment can influence the chance of regrowth in non‑scarring conditions. Our overview of alopecia types: causes, warning signs and what can help explains how clinicians separate these patterns.

Dermatologists generally advise prompt assessment for new painful bumps, spreading crusts or patchy shedding, because early anti‑inflammatory treatment can limit follicle damage. Swabs and, if needed, a biopsy can be helpful when scarring alopecia is suspected on examination.

Self‑care can support medical treatment. BAD suggests antiseptic or tar‑containing shampoos may reduce inflammation or bacterial load, avoiding scratching to prevent worsening, and monitoring for signs of flare. Ubiehealth.com recommends regular cleansing, not sharing combs, rinsing after swimming and avoiding heavy oils or gels that occlude the scalp.

Gentle handling of hair is sensible while the scalp is inflamed. People often find wide‑tooth combs and low‑tension styles reduce breakage and discomfort. If tight styles have contributed to irritation, avoid them; our guide to traction alopecia: spotting hair loss caused by tight styles outlines what to change and why.

For those unsure about the amount of daily shedding, our explainer on how much hair loss is normal — and when to worry covers usual ranges and the timing of stress‑related shedding, which can help separate temporary from scarring problems.