Folliculitis is a common skin condition in which hair follicles become inflamed. It’s usually caused by a bacterial or fungal infection. At first it may look like small red bumps or white-headed pimples around hair follicles — the tiny pockets from which each hair grows. The infection can spread and turn into nonhealing, crusty sores.
The condition isn’t life-threatening, but it can be itchy, sore and embarrassing. Severe infections can cause permanent hair loss and scarring.
If you have a mild case, it’ll likely clear in a few days with basic self-care measures. For more serious or recurring folliculitis, you may need to see a doctor.
Certain types of folliculitis are known as hot tub rash, razor bumps and barber’s itch.
Folliculitis is caused by an infection of hair follicles, usually from the bacteria Staphylococcus aureus. Folliculitis may also be caused by viruses, fungi and even an inflammation from ingrown hairs.
The condition is classified as either superficial or deep, based on how much of the hair follicle it involves. Deep folliculitis is usually more severe.
Follicles are densest on your scalp, and they occur everywhere on your body except your palms, soles, lips and mucous membranes. Damaged follicles are at risk of infection.
The most common causes of follicle damage are:
- Friction from shaving or tight clothing
- Heat and sweat, such as that caused by wearing rubber gloves or waders
- Certain skin conditions, such as dermatitis and acne
- Injuries to your skin, such as from scrapes or surgical wounds
- Coverings on your skin, such as plastic dressings or adhesive tape
Folliculitis signs and symptoms include:
- Clusters of small red bumps or white-headed pimples that develop around hair follicles
- Pus-filled blisters that break open and crust over
- Red and inflamed skin
- Itchy or burning skin
- Tenderness or pain
- A large swollen bump or mass
When to see a doctor
Make an appointment with your doctor if your condition is widespread or the signs and symptoms don’t go away after a few days. You may need an antibiotic or an antifungal medication to help control the problem.
Types of superficial folliculitis
Superficial forms of folliculitis include:
- Bacterial folliculitis. This common type is marked by itchy, white, pus-filled bumps. When bacterial folliculitis affects a man’s beard area, it’s called barber’s itch. It occurs when hair follicles become infected with bacteria, usually Staphylococcus aureus (staph). Staph bacteria live on the skin all the time. But they generally cause problems only when they enter your body through a cut or other wound.
- Hot tub folliculitis (pseudomonas folliculitis). This type is caused by pseudomonas bacteria. You may be exposed to these bacteria in many places, including hot tubs and heated pools in which the chlorine and pH levels aren’t well-regulated. You may develop a rash of red, round, itchy bumps one to four days after exposure. These may later develop into small pus-filled blisters (pustules).
The rash is likely to be worse in areas where your swimsuit held contaminated water against the skin or where skin — such as the back of the thighs — came in direct contact with a contaminated surface.
- Barber’s itch (pseudofolliculitis barbae). This is an inflammation caused by ingrowing hairs. It mainly affects black men who shave and is most noticeable on the face and neck. People who get bikini waxes may develop barber’s itch in the groin area. This condition may leave dark raised scars (keloids).
- Pityrosporum (pit-ih-ROS-puh-rum) folliculitis. This type is especially common in teens and adult men. It’s caused by a yeast infection and produces chronic, red, itchy pustules on the back and chest and sometimes on the neck, shoulders, upper arms and face.
Types of deep folliculitis
Deep folliculitis, where the whole hair follicle is involved, comes in various forms:
- Sycosis barbae. This type affects men who have begun to shave. At first, small pustules appear on the upper lip, chin and jaw. They become more prevalent over days and weeks as shaving continues. Severe sycosis barbae may cause scarring.
- Gram-negative folliculitis. This type sometimes develops if you’re receiving long-term antibiotic therapy for acne. Antibiotics alter the normal balance of bacteria in the nose. This leads to an overgrowth of harmful organisms called gram-negative bacteria. In most people, this doesn’t cause problems, and the bacteria in the nose return to normal once antibiotics are stopped. In a few people, the gram-negative bacteria spread to the skin around the nose and mouth. This can cause new, severe acne.
- Boils (furuncles) and carbuncles. These occur when hair follicles become deeply infected with staph bacteria. A boil usually appears suddenly as a painful pink or red bump. The surrounding skin also may be red and swollen. The bump then fills with pus and grows larger and more painful before it finally ruptures and drains. Small boils usually heal without scarring. A large boil may leave a scar.
- A carbuncle is a cluster of boils. It usually appears on the back of the neck, shoulders, back or thighs. A carbuncle causes a deeper and more severe infection than does a single boil. As a result, it develops and heals more slowly and is likely to leave a scar.
- Eosinophilic (e-o-sin-o-FILL-ik) folliculitis. This type mainly affects people with HIV/AIDS. Symptoms include intense itching and recurring patches of inflamed, pus-filled sores on the scalp, face, neck and upper chest. The sores usually spread and often leave areas of darker than normal skin (hyperpigmentation) when they heal. The exact cause of eosinophilic folliculitis isn’t known. But it may involve the same yeast-like fungus responsible for pityrosporum folliculitis.