Folliculitis is a common skin condition characterized by inflammation of the hair follicles. This inflammation typically results in small, red bumps or pus-filled pimples (pustules) centered around a hair. While usually not a serious health concern, folliculitis can be itchy, sore, and sometimes mistaken for acne. Successful treatment requires identifying the underlying cause, as the condition can be triggered by infection or simple irritation.
Understanding the Causes of Folliculitis
Folliculitis develops when the hair follicle is damaged, making it susceptible to invasion by microorganisms or blockage. The most frequent infectious cause is bacterial, often involving Staphylococcus aureus (staph). This infection commonly occurs after skin trauma, such as shaving, or when follicles are blocked by oils or tight clothing.
Other infectious agents can also cause inflammation. Fungal folliculitis is often caused by yeasts like Malassezia, leading to a persistent, itchy rash, especially on the upper trunk. Viruses, such as Herpes simplex, can occasionally cause folliculitis, presenting as clusters of small blisters.
Folliculitis is not always caused by infection; non-infectious types are common. Mechanical irritation from shaving, which results in ingrown hairs, is a frequent cause known as pseudofolliculitis barbae. Chemical exposure, skin occlusion from heavy creams, or prolonged use of certain medications like topical steroids can also trigger inflammation. Only bacterial forms respond to antibiotic treatment.
Topical and Oral Antibiotic Treatment Options
Antibiotics are the treatment of choice for folliculitis confirmed or suspected to be bacterial. Medication selection depends on the severity and extent of the infection. For superficial or localized bacterial folliculitis, topical antibiotics are generally the first line of defense to minimize the risk of widespread resistance.
Topical agents like mupirocin ointment or clindamycin lotion are commonly prescribed. These are typically applied directly to the affected areas two or three times a day for five to ten days. Benzoyl peroxide washes are an alternative and may be recommended for use in the shower for up to a week to help reduce bacterial colonization.
Oral antibiotics become necessary when the infection is widespread, involves deeper parts of the hair follicle, or fails to clear with topical treatment. Common first-line oral medications include cephalexin or dicloxacillin, which are effective against Staphylococcus aureus. A typical treatment course involves taking 250 to 500 mg, three to four times daily, for about ten days.
If the bacteria are resistant to initial treatments, or if a different organism is suspected, other oral antibiotics may be used. Options for resistant strains, such as methicillin-resistant Staphylococcus aureus (MRSA), include trimethoprim/sulfamethoxazole or doxycycline. For “hot tub folliculitis,” caused by Pseudomonas aeruginosa, a specific oral antibiotic like ciprofloxacin may be needed, although mild cases often resolve without medication.
Addressing Non-Bacterial Folliculitis
A significant portion of folliculitis cases will not respond to antibiotics because they are caused by fungi, viruses, or simple irritation. For fungal folliculitis, particularly that caused by Malassezia yeast, antifungal agents are required. Topical antifungal creams or shampoos containing ingredients such as ketoconazole are often used initially.
If the fungal infection is extensive or persistent, oral antifungal medications like fluconazole may be prescribed. These treatments target the organism directly, making antibiotics ineffective against this type of inflammation. Viral folliculitis, a less common presentation, may be linked to the Herpes simplex virus.
Treatment for viral cases typically involves oral antiviral drugs, such as acyclovir, valacyclovir, or famciclovir. Many mild cases of viral folliculitis may resolve spontaneously, but medication can accelerate healing and reduce the risk of spread. Non-infectious folliculitis, such as that caused by shaving irritation, is managed by removing the source of the trauma. This type often improves with simple measures like warm compresses and avoiding the irritant, without the need for medication.
Strategies for Preventing Recurrence
Preventing the return of folliculitis involves consistent hygiene and modification of skin care habits. Regular cleansing with an antibacterial wash, such as a benzoyl peroxide product, helps reduce the bacterial population on the skin. Use a clean towel and washcloth for each use, and launder all bedding and clothing frequently in hot, soapy water.
Avoiding friction and heat is an important preventative step, as these factors can damage the hair follicle and trap moisture. Wearing loose-fitting, breathable clothing, especially in humid environments or during physical activity, prevents sweat and bacteria from being held against the skin. Those who shave should always use a sharp, clean blade and shave in the direction of hair growth to minimize follicular trauma.
In cases of chronic, recurring bacterial folliculitis, the source may be a persistent bacterial reservoir. Staphylococcus aureus often colonizes the nasal passages, and treating this carrier state is sometimes necessary to prevent ongoing skin infections. Decolonization typically involves applying mupirocin ointment inside the nostrils twice daily for a short course. Ensuring hot tubs are properly chlorinated and maintained is also an effective preventative measure.