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Diseases and Conditions
Special to CNN.com
With common names like hot tub folliculitis and barber's itch, folliculitis may sound more like a bad joke than a skin disorder. But folliculitis, an infection of the hair follicles, is no laughing matter. Severe cases may cause permanent hair loss and scarring, and even mild folliculitis can be uncomfortable and embarrassing.
Folliculitis usually appears as small, white-headed pimples around one or more hair follicles — the tiny pockets from which each hair grows. Most infections are superficial, and they may itch, but on occasion they're painful. Superficial folliculitis often clears by itself in a few days, but deep or recurring folliculitis may need medical treatment.
Signs and symptoms
The signs and symptoms of folliculitis vary, depending on the type of infection. In forms of the disorder that affect the upper part of the hair follicle (superficial folliculitis), signs and symptoms include:
- Clusters of small red bumps that develop around hair follicles
- Pus-filled blisters that break open and crust over
- Itchiness or tenderness
Deep folliculitis starts deeper in the skin surrounding the hair follicle and affects the entire hair follicle. Signs and symptoms of deep folliculitis include:
- A large swollen bump or mass
- Pus-filled blisters that break open and crust over
- Possible scars once the infection clears
Superficial forms of folliculitis include:
- Staphylococcal folliculitis. This common type of folliculitis is marked by itchy, white, pus-filled bumps that can occur anywhere on your body. When it affects the beard area of men, it's called barber's itch. It occurs when hair follicles become infected with Staphylococcus aureus (staph) bacteria. Although staph bacteria live on your skin all the time, they generally cause problems only when they enter your body through a cut or other wound. This can occur through shaving or with an injury to the skin.
- Pseudomonas folliculitis (hot tub folliculitis). The pseudomonas bacteria that cause this form of folliculitis thrive in a wide range of environments, including hot tubs whose chlorine and pH levels aren't well regulated. Within eight hours to five days of exposure to the bacteria, a rash of red, round, itchy bumps will appear that later may develop into small pus-filled blisters (pustules). The rash is likely to be worse in areas where your swimsuit holds contaminated water against your skin. You're at increased risk of infection if you have diabetes, a history of skin infections, or open cuts or sores.
- Tinea barbae. Caused by a fungus rather than a bacterium, this type of folliculitis develops in the beard area in men, causing itchy, white bumps. The surrounding skin also may become reddened. A more serious, inflammatory form of the infection appears as pus-filled nodules that eventually form a crust and that may occur along with swollen lymph nodes and fever.
- Pseudofolliculitis barbae. An inflammation of the hair follicles in the beard area, pseudofolliculitis barbae affects men with curly beards. It develops when shaved hairs curve back into the skin, leading to inflammation and, in rare cases, to dark raised scars (keloid scars) on the face and neck.
- Pityrosporum folliculitis. Especially common in young and middle-aged adults, pityrosporum folliculitis produces chronic, red, itchy pustules on the back and chest and sometimes on the neck, shoulders, upper arms and face. It's caused by the yeast-like fungus.
- Herpetic folliculitis. Shaving through a cold sore — a small, fluid-filled blister caused by the herpes simplex virus — can sometimes spread the herpes infection to neighboring hair follicles.
Types of deep folliculitis include:
- Gram-negative folliculitis. This sometimes develops in people receiving long-term antibiotic treatment for acne. Antibiotics alter the normal balance of bacteria in the nose, leading to an overgrowth of harmful organisms (gram-negative bacteria). In most people, this doesn't cause problems, and the flora in the nose returns to normal once antibiotics are stopped. In a few people, however, gram-negative bacteria spread to the cheeks, chin and jaw line, where they cause new, sometimes-severe acne lesions.
- Boils 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 about 1/2 inch in diameter. The surrounding skin also may be red and swollen. Within 24 hours, the bump fills with pus. It grows larger and more painful for five to seven days, sometimes reaching golf ball size before it develops a yellow-white tip that finally ruptures and drains. Boils generally clear completely in about two weeks. Small boils usually heal without scarring, but a large boil may leave a scar. A carbuncle is a cluster of boils that often occurs on the back of the neck, shoulders or thighs, especially in older men. Carbuncles cause a deeper and more severe infection than does a single boil. As a result, they develop and heal more slowly and are likely to leave scars.
- Eosinophilic folliculitis. Seen primarily in HIV-positive people, this type of folliculitis is characterized by recurring patches of inflamed, pus-filled sores, primarily on the face and sometimes on the back or upper arms. The sores usually spread, may itch intensely and often leave areas of darker than normal skin (hyperpigmentation) when they heal. The exact cause of eosinophilic folliculitis isn't known, although it may involve the same yeast-like fungus responsible for pityrosporum folliculitis.
Every hair on your body grows from a follicle, a small pocket of modified skin. Although follicles are densest on your scalp, they occur everywhere except your palms, soles and mucous membranes, such as your lips.
Each follicle is attached to a small muscle. When you're cold or frightened, the muscle contracts, raising the hairs above the level of your skin and giving the appearance of goose bumps. Just above these muscles are sebaceous glands that produce an oil (sebum) that lubricates your skin and coats each hair shaft. Sebum is carried to the follicles and skin in tiny ducts.
Normally, the follicles carry out these functions with few problems. But when they're damaged, they may be invaded by viruses, bacteria or fungi, leading to infections such as folliculitis.
The most common causes of hair follicle damage include:
- Friction from shaving or tight clothing
- Excessive perspiration
- Inflammatory skin conditions, including dermatitis and acne
- Injuries to your skin, such as abrasions or surgical wounds
- Covering your skin with plastic dressings or adhesive tape
- Exposure to coal tar, pitch or creosote — common among roofers, mechanics and oil workers
Anyone can develop folliculitis, but certain factors make you more susceptible to the condition. These include:
- Medical conditions that reduce your resistance to infection, such as diabetes, chronic leukemia, organ transplantation and HIV/AIDS
- A pre-existing skin condition, such as acne or dermatitis
- Trauma to your skin from surgery
- Long-term antibiotic therapy for acne
- Topical corticosteroid therapy
- Obesity — folliculitis is more common in people who are overweight
- Living in a warm, humid climate
When to seek medical advice
Mild cases of folliculitis often clear up without any treatment. But if the infection doesn't improve in two or three days, appears to spread or recurs often, call your doctor or a dermatologist. You may need antibiotics or antifungal medications to help control the problem.
Screening and diagnosis
Your doctor is likely to diagnose folliculitis simply by looking at your skin. When standard treatments fail to clear the infection, your doctor may send a sample taken from one of your pustules to a laboratory, where it's grown on a special medium (cultured) and then checked for the presence of bacteria. When doctors suspect eosinophilic folliculitis, they may remove a small tissue sample (biopsy) from an active lesion for testing.
Mild cases of folliculitis aren't likely to cause complications, although the infection may recur or spread, leading to large, itchy patches of staph infection on the skin (plaques).
Complications of severe folliculitis may include:
- Cellulitis. This potentially serious bacterial infection appears as a swollen, red area of skin that feels hot and tender and that may spread rapidly. It's most common on your legs, arms or face. Although the initial infection may be superficial, it eventually can affect the tissues underlying your skin or spread to your lymph nodes and bloodstream.
- Furunculosis. This condition occurs when a number of boils develop under your skin. Boils usually start as small red bumps but become larger and more painful as they fill with pus.
- Scarring. Severe folliculitis may leave thick, raised scars (hypertrophic or keloid scars) or patches of skin that are darker than normal.
- Destruction of the hair follicle. This leads to permanent hair loss.
For some, folliculitis goes away without medical treatment within two to three days. During that time, self-care measures, such as warm compresses and anti-itch creams, can help relieve your symptoms.
Persistent or recurring cases are likely to require treatment. The therapy your doctor recommends will depend on the type and severity of your infection.
- Staphylococcal folliculitis. Your doctor may prescribe an antibiotic that you apply to your skin (topical) or that you take by mouth (oral). Your doctor may also recommend that you avoid shaving the affected area until the infection heals. If you must shave, use an electric razor or clean razor blade every time.
- Pseudomonas folliculitis (hot tub folliculitis). Hot tub folliculitis rarely requires specific treatment, although your doctor may prescribe an oral or topical medication to help relieve itching (anti-pruritic). More serious cases may require an oral antibiotic.
- Tinea barbae. This infection — especially the inflammatory form — can be effectively treated with oral antifungal medications.
- Pseudofolliculitis barbae. Self-care measures are the best treatments for this condition. Shaving with an electric razor, which doesn't cut as closely as a razor blade does, can help. If you do use a blade, massage your beard area with a warm, moist washcloth or facial sponge to lift the hairs so that they can be cut more easily. Use a shaving gel instead of cream, and shave in the direction of the hair growth. When you're finished, rinse thoroughly with warm water and apply a moisturizing after-shave. If these measures don't help, your doctor may prescribe the acne medication tretinoin (Retin-A).
- Pityrosporum folliculitis. Topical or oral antifungals are the most effective treatments for this type of folliculitis. Because the condition often returns once you've finished the course of oral medication, your doctor may recommend using topical ointments indefinitely. Antibiotics aren't helpful in treating pityrosporum folliculitis and may make the infection worse by upsetting the normal balance of bacteria on your skin.
- Herpetic folliculitis. If you're a healthy adult, herpetic folliculitis may clear without treatment in seven to 10 days. But if you're living with HIV/AIDS or you experience frequent cold sores, your doctor may prescribe an oral antiviral medication such as acyclovir, famciclovir or valacyclovir. Although these drugs can clear the infection, they won't necessarily prevent it from recurring. They also may cause side effects such as headache, diarrhea, nausea and abdominal pain.
- Gram-negative folliculitis. Although this type of folliculitis results from long-term antibiotic therapy for acne, it's usually treated with certain antibiotics or with isotretinoin (Accutane).
- Boils and carbuncles. Your doctor may drain a large boil or carbuncle by making a small incision in the tip. This relieves pain, speeds recovery and helps lessen scarring. Deep infections that can't be completely cleared may be covered with sterile gauze so that pus can continue to drain. Sometimes your doctor may prescribe antibiotics to help heal severe or recurrent infections.
- Eosinophilic folliculitis. A number of therapies are effective against eosinophilic folliculitis, but topical corticosteroids are often the treatment of choice. Your doctor may prescribe a short course of oral corticosteroids if you have a severe infection. All steroids can have serious side effects and should be used for as brief a time as possible. If you're living with HIV/AIDS and have mild eosinophilic folliculitis, your doctor may prescribe topical steroids in conjunction with oral antihistamines. More severe cases may require treatment with isotretinoin (Accutane) for several months.
Although it's not always possible to prevent folliculitis, these measures may help keep you infection-free:
- Avoid constrictive clothing. Tight clothes — especially jeans and athletic wear — may be stylish, but make sure they don't chafe your skin.
- Shave with care. Use an electric razor or a new blade every time you shave. Be especially careful to keep the shaved area clean and to avoid cuts and nicks. If you're a woman who gets frequent infections, you may want to consider depilatories or other methods of hair removal.
- Maintain hot tubs. If you own a hot tub, clean it regularly and add chlorine when recommended. Use commercial tubs only if you're sure they're well maintained.
Mild cases of folliculitis often respond well to home care. The following suggestions may help relieve discomfort, speed healing and prevent the infection from spreading:
- Apply a warm, moist washcloth or compress to the affected area several times a day.
- Try an oatmeal lotion or an over-the-counter hydrocortisone cream to help soothe itchy skin.
- Gently wash the infected skin twice a day with antibacterial soap or apply an over-the-counter antibiotic ointment.
- Avoid shaving irritated skin. If you must shave, use an electric razor rather than a blade, and apply a soothing after-shave lotion when you're finished.
- To help a boil or carbuncle burst and drain more quickly, apply a soft cloth soaked in warm salt water to the affected area for about 30 minutes several times a day. Prepare the salt water by adding 1 teaspoon of salt to 1 quart of boiling water. Let cool until comfortably warm.
- Don't share your towels or washcloths, and launder them in plenty of hot, soapy water after every use. Wash clothes that cover the affected areas after each wearing.