6 Possible Causes Of Folliculitis You Should Know

causes of folliculitis

Are you troubled by pustules, pimples, or an itchy rash? You may have folliculitis, a condition in which your hair follicles become inflamed. Folliculitis can develop in any area where you have hair, including your back, chest, buttocks, legs, and arms.1 Let’s take a look at some factors that can cause this common problem.

6 Possible Causes Of Folliculitis

1. Infection

Various viruses, fungi, bacteria, and parasites can infect you and cause folliculitis.



The Staphylococcus aureus bacteria are usually responsible for bacterial folliculitis. The bacteria can infect hairy areas like the beard in a condition called folliculitis barbae. This is more common among men who shave, with contaminated shaving equipment leading to infection. Also, reinfection is not uncommon, particularly among men who have conditions like hay fever, sinusitis, or nasal discharge. This happens when bacteria that live in the nose infect hair follicles.2

A variety of folliculitis known as hot tub folliculitis, which usually develops on the trunk, is caused by Pseudomonas aeruginosa. These bacteria are usually found in spas or hot tubs that have not been properly sanitized.


A rare kind of folliculitis known as gram-negative folliculitis, caused by gram negative bacteria which affect the face, usually develops after antibiotics are used to treat acne.3


The herpes simplex virus, which causes herpes or cold sores, can sometimes cause folliculitis too. It is usually seen in men who suffer from recurrent facial herpes infections and who use razors.


Herpes zoster, the virus that causes shingles, can also cause folliculitis.

Another virus known as Molluscum contagiosum, which is commonly found in children, can cause this condition. You usually see papules clustered around a body fold in this case.



Yeasts, which are a kind of fungi, can cause folliculitis. The most common yeast that causes folliculitis is known as Malassezia, causing an acne-like itch rash on the chest or back of young adults. Meanwhile, another yeast called Candida albicans causes the development of folliculitis in the folds of your skin or beard.

Ringworm of the scalp (Tinea capitis), which is the result of a fungal infection, generally causes hair loss and scaly skin. Sometimes, it can lead to folliculitis too.



Infestation by parasites like Demodex and Sarcoptes scabiei can result in folliculitis. Demodex generally infests the scalp or face of elderly people or people whose immune system has been weakened. Sarcoptes scabiei is responsible for causing scabies.

2. A Close Shave

If beard hair is cut too short, it can curl back and enter your skin, causing inflammation. This condition usually affects the beards of men with curly hair. This is similar to folliculitis barbae but without the infection and is, therefore, called pseudofolliculitis barbae.4


3. Skin Irritation

Some substances and practices can irritate and damage hair follicles, block them, and cause folliculitis.


Irritation of the skin due to friction can lead to folliculitis. This is generally seen in women or men who shave their legs or faces using a razor, especially if the shave goes against the direction of hair growth. This kind of folliculitis is also associated with wearing tight clothes or being obese.


Blocked Pores

Topical application of products like moisturizers, oils, and ointments can block the hair follicle opening and lead to folliculitis. Some products may also cause your skin to swell. This may block the follicle opening and lead to inflammation.

Reaction To Chemicals

Topical products containing coal tar and other chemicals can irritate your skin and cause folliculitis. Some topical medicines like corticosteroids can also cause swelling and obstruct your follicular opening, particularly when used on the face.

4. Medication

Many medicines can induce folliculitis too. Some examples include oral corticosteroids, epidermal growth factor receptor inhibitors, androgenic hormones, and lithium.

5. Weakened Immunity

A weakened immune system can leave you more susceptible to folliculitis. A particular kind of folliculitis known as eosinophilic folliculitis is a rare and recurrent skin disorder that specifically arises in people whose immune system has been compromised, say those with HIV or cancer. 5

6. Skin Conditions

Various skin conditions can cause folliculitis. Some of them include:

Lichen Planus

A skin condition characterized by an itchy non-infectious rash that can affect various body parts like arms, trunk, legs, genitals, mouth, nails etc.6

Discoid Lupus Erythematosus

A chronic skin condition that results in sores, scarring, and inflammation. It generally develops on the ears, face, and scalp though other body parts can be affected too.7

Folliculitis Decalvans

A chronic inflammatory skin condition that develops on the scalp, though other areas like beards, armpits, legs etc. can sometimes be affected too. Itchiness, scarring, and hair loss can be indicative of this condition.8

Acne Nuchae Keloidalis

An inflammatory condition that develops when the hair on your nape or the back of your head grows into the skin, irritates the follicles, and leads to inflammation. This condition is more commonly seen in people with dark skin and curly hair.9

Unknown Causes

In some cases of folliculitis, a cause cannot be identified – for instance, buttock folliculitis commonly affects the buttocks in men as well as women. Although this is thought to have a bacterial origin, the specific offender is yet unknown.10

What Can You Do About Folliculitis?

The treatment for folliculitis depends on its cause. Antibiotics may be prescribed for conditions caused by bacteria while antifungal medication can be helpful if it’s caused by fungi. You can also try applying a moist hot compress to drain affected follicles. Reduce or avoid chances of skin friction by wearing comfortable clothes and not shaving.11