Folliculitis: Infected Hair Follicles

What does folliculitis look like?

Folliculitis is inflammation of hair follicles. It appears as small red bumps or pustules, each centred on a hair, and it is most common on the scalp, beard area, back, chest, buttocks, and legs. Many people treat it as acne for months without improvement, because the two look alike at a glance but do not respond to the same treatment. Identifying the cause is what makes folliculitis treatable.

The main types, and why the differences matter

Bacterial folliculitis, usually caused by staphylococci, produces tender pustules and may follow shaving, plucking, or friction from clothing. Yeast folliculitis, caused by the same Malassezia yeast involved in seborrhoeic dermatitis, tends to itch more than it hurts and is often widespread on the back and chest. Gram-negative folliculitis can appear after prolonged antibiotic treatment for acne. A hot-tub or spa exposure can produce a distinctive eruption within days. When follicles are inflamed more deeply, a furuncle or carbuncle forms: a painful, firm, enlarging nodule that needs medical treatment. Recurrent boils in the armpits or groin may instead be a different disease, hidradenitis suppurativa, which is managed quite differently.

Why sampling decides the treatment

Sampling is what separates the types. A swab of pus sent for bacterial culture identifies the organism and, importantly, its antibiotic sensitivities when infection is recurrent or resistant. A scraping examined under the microscope detects yeast forms. When folliculitis is deep, recurrent, or fails to respond, a skin biopsy can confirm the pattern and exclude other conditions. In recurrent bacterial infection, nasal or skin carriage of staphylococci may need to be addressed alongside the skin itself.

Treatment classes

Limited bacterial folliculitis is treated with topical antibacterial preparations, with oral antibiotics reserved for extensive or deep infection and chosen according to culture results. Yeast folliculitis responds to topical or oral antifungal therapy, not to antibacterials. Measures that reduce friction, occlusion, and shaving trauma are part of every plan, and antiseptic washes are used selectively to avoid irritation and resistance.

The mechanism behind recurrent crops

When folliculitis keeps coming back, there is normally a reason: shaving technique against the grain, occlusive sportswear, a hot tub, an inadequately treated course of antibiotics, or a reservoir of bacteria on the skin or in the nose. Treating each crop in isolation without addressing the mechanism produces an endless cycle. Culture-guided treatment plus a change in the provoking habit is what actually ends it.

Follow-up and honest limits

Superficial folliculitis usually settles within one to two weeks of correct treatment. Deep infection takes longer and may leave scarring or pigment change. People with recurrent disease may need a longer maintenance plan, and resistance to commonly used antibiotics is a genuine and growing problem that makes culture-guided treatment more important rather than less.

When should it be reviewed promptly?

A bump that becomes large, firm, increasingly painful, or is accompanied by fever or spreading redness needs prompt review, because deep infection may need drainage and systemic treatment. Boils that keep recurring in the armpits, groin, or under the breasts, or that form tunnels and scars, may be a chronic condition requiring specialist management. Folliculitis that is extensive, follows a hot tub or spa, or appears while you are taking antibiotics or are immunosuppressed should also be reviewed, because the cause and treatment differ in each case.