Folliculitis

What is folliculitis?

In folliculitis, the hair follicles become inflamed. It causes small bumps or pus spots, each centred on a hair. It can affect any hair-bearing skin and can be short-lived or recurrent and long-lasting.

Who gets it?

Folliculitis is very common and can affect anyone. It is more common in people who shave or wax, wear tight clothing, sweat a lot, are overweight, have diabetes or a weakened immune system, or use hot tubs. Boils are also more common in teenagers.

What causes it?

Folliculitis has several causes.

Bacterial folliculitis is most often caused by Staphylococcus aureus, a bacterium that many people carry harmlessly in the nose. Hot tub folliculitis is caused by a different bacterium, Pseudomonas, which can grow in poorly maintained hot tubs and pools.

Yeast folliculitis, also called Malassezia or pityrosporum folliculitis, causes itchy, uniform small spots on the upper back, chest and shoulders, and is often mistaken for acne. It is more common in hot, humid conditions and after antibiotics.

Irritant folliculitis results from friction, shaving, waxing, tight clothing or occlusive products.

Pseudofolliculitis barbae, sometimes called razor bumps, occurs when shaved hairs curl back and grow into the skin. It is particularly common in people with tightly curled hair, especially in the beard area. A related condition, acne keloidalis nuchae, causes firm bumps and scarring on the back of the neck and scalp.

Rarer types of folliculitis are associated with certain medicines or with a weakened immune system.

Is it hereditary or contagious?

Folliculitis is not inherited, although the tendency to razor bumps is related to hair type. Bacterial folliculitis and boils can spread through skin contact and shared towels, razors or clothing, and some people carry Staphylococcus long term in the nose, armpits or groin. Most other types of folliculitis are not contagious.

What does it look and feel like?

Folliculitis causes small, raised spots or pus spots around hair follicles, often in clusters. They may be red on lighter skin and darker or skin-coloured on brown and black skin. They can be itchy, tender or sore. Common sites include the beard area, scalp, neck, chest, back, buttocks, thighs and legs.

Deeper infection of a follicle can form a painful, swollen boil (furuncle), and several connected boils form a carbuncle. Recurrent or long-standing folliculitis can leave dark marks and, in some types, scarring and permanent hair loss.

How is it diagnosed?

Folliculitis is usually diagnosed from its appearance. A swab from a pus spot, or skin scrapings, may be taken to identify the cause, particularly if it keeps coming back. Your dermatologist may also check whether you carry Staphylococcus in your nose.

What are the treatment options?

Dr Mounsey will establish the type of folliculitis, which may involve taking swabs to look for bacteria or yeast. Treatment depends on the cause and can include antiseptic washes, antibiotic or antifungal creams, and courses of antibiotic or antifungal tablets. For folliculitis linked to shaving, he will advise on shaving technique and hair removal options. Recurrent bacterial infections may need treatment to clear bacteria carried in the nose.

What is the outlook?

Most folliculitis is mild and settles once the cause is identified and addressed. Recurrent folliculitis can be persistent, and finding the underlying type is the key to managing it.

More information

British Association of Dermatologists patient leaflet on boils: https://www.bad.org.uk/pils/boils

This page gives general information only and is not a substitute for a consultation. Everyone's skin is different, and what is right for you will depend on your own circumstances. If you are worried about a skin problem, please book an appointment with Dr Mounsey or speak to your GP. If you have a mole or skin lesion that is changing, bleeding or growing quickly, please seek medical advice promptly.