Overview

Folliculitis is a skin condition caused by an infection of your hair follicles. This can result in a bumpy red rash on your skin that may cause itching and discomfort. It is a common condition that can often be treated with proper hygiene practices. 

There are various types of folliculitis which will be covered in this article. Advice for managing your symptoms will be provided below. However, please seek professional medical assistance if you are concerned about any changes in your health.

The importance of hair follicles

To understand folliculitis, it is first important to appreciate your hair follicles. Hair follicles are microscopic holes in your skin that surround each strand of hair.  They are generally found in the upper layers of your skin. As they enter the dermis layer, your hair follicles have a good blood supply and neural connections.¹ They are also associated with sebaceous glands, responsible for releasing sebum.  

You have hair follicles all over your body. They are important structures in your skin as they contain stem cells. Follicles regulate the environment around your stem cells and protect them until they are needed. These stem cells, as well as supporting hair growth, have a range of functions. This includes wound healing and the formation of new blood vessels (angiogenesis).¹

There are two categories to describe the severity of folliculitis: 

• Superficial folliculitis affects the epidermis area of the follicle 
• Deep folliculitis describes an infection of the whole follicle

Causes

When pathogenic microorganisms enter your hair follicles, your body produces a reaction to remove them. One of these natural defence mechanisms is known as inflammation.  Whilst the inflammatory process can be helpful, it can also affect your healthy cells if it continues for a long time. Damage to cells within the hair follicle can cause symptoms of folliculitis.² 

Pathogens that can infect your hair follicles include:

• Bacteria
• Fungi
• Viruses
• Parasites

Folliculitis can also be caused by the irritation of the follicles, which may be caused by ingrown hair growth.³

It is important to understand the different causes of folliculitis as they determine the type of treatment that will be most suitable.

Bacteria

Most cases of folliculitis are caused by a single type of bacteria known as Staphylococcus aureus. This type of bacteria lives on the surface of your skin. It is harmless unless it enters your body. Folliculitis caused by Staphylococcus aureus is usually due to a build-up of sweat and bacteria on the skin which can block the hair follicles. 

Another strain of bacteria that causes folliculitis is Pseudomonas aeruginosa. This type of bacteria generally lives in water and soil. They may enter the hair follicles if your skin is exposed to unclean surfaces in swimming pools and hot tubs. This makes it known as hot-tub folliculitis.

Gram-negative folliculitis is thought to be caused by other species of bacteria such as some strains of Enterobacter and Klebsiella. These bacteria tend to increase after long-term antibiotic treatment.²

Fungi

Fungal folliculitis is most commonly seen during puberty when the sebaceous glands are more active due to increased hormone levels. This means that they overproduce sebum. Increased sebum levels can make the skin appear oily.

Sebum is broken down by a type of fungus called Malassezia. The products of sebum digestion can block your hair follicles.⁴ This can result in pityrosporum folliculitis.

Viruses

The herpes simplex virus has been reported to cause folliculitis in some people. It typically presents on the face and is often incorrectly diagnosed as it can be mistaken for other forms of folliculitis.⁵

Human immunodeficiency virus (HIV) causes AIDS, a disease that decreases the amount of a specific type of white blood cell known as CD4 or helper T cells. This virus itself does not cause folliculitis. However, a reduced immune response in these patients has been linked to instances of folliculitis.^2,6 This type of folliculitis, known as eosinophilic folliculitis, is therefore common in people with low levels of CD4 cells. 

Parasites

Demodex (face mites) typically live within the hair follicles on human skin. They eat dead skin cells. The mites have mostly been noted to be present on the face, such as in your eyelashes and around your nose. They have been estimated to be present in the majority of the human population.⁷ 

For most people, Demodex mites will not cause any problems. Issues start to arise when the reproduction rate of the mites becomes uncontrolled. 

High levels of Demodex mites can be caused by various factors, such as:

• Clogged pores and hair follicles- either from excessive product use or oily skin
• Use of immunosuppressants 
• Diseases that affect the immune system, such as HIV and diabetes mellitus

Symptoms

Symptoms of folliculitis are generally the same regardless of the type of infection. This can include:

• Clusters of pimples that may look like acne
• Pustules (white or yellow pus-filled bumps)
• Itching or burning sensations around the affected area(s)
• Boils (swollen, painful, red bumps) that could indicate deep folliculitis

Commonly affected areas include the neck, back, groin, and face.^2,3,5,7

It may be tempting to pop any pimples you may get. Please avoid doing this as the pus could contain more contagious pathogens. This could cause your infection to spread to more areas of your body or other people. 

Treatment

• Superficial folliculitis can be easily resolved by cleansing the affected areas with warm, soapy water
• You can also purchase anti-inflammatory medications and antihistamines to relieve your symptoms
• In some cases, you will be required to take medication prescribed by a physician or dermatologist. The type of medication will depend on the cause of the infection. For example, bacterial folliculitis can be treated with antibiotics. These can be applied to the skin or taken orally in extreme cases²
• Antibiotics will not have an effect on fungal, viral, or parasitic infections

Your doctor will be able to determine the type of infection you have by conducting swabs, skin biopsies, or blood tests. 

Prevention

There are many easy steps you can take to prevent any type of folliculitis. 

• The first answer would be to implement a regular skincare routine. It doesn’t have to be a complicated 20-step routine full of expensive products. You can learn more about creating a skincare plan that works for you here
• You can also control the spread of pathogens by taking a bath or shower at least once every few days, or after any physical activity. You should wash your clothes, towels, and bedsheets regularly
• Shaving may also increase the risk of folliculitis.³ Your hair follicles can become irritated as the hair tries to regrow. You can reduce this risk by shaving less frequently. If you must shave, make sure that you clean the area you want to shave. Also, clean your shaving tools after use and avoid sharing them with others
• Avoid using hot tubs or swimming pools if they look dirty or haven’t been chemically treated
• You can reduce your risk of developing folliculitis by maintaining a healthy diet. Alongside many other benefits, keeping a good control of your blood sugar and cholesterol levels minimises the strain on your white blood cells.⁸ This means that your immune system can work more efficiently

FAQs

Does folliculitis damage hair follicles?

Damage to your hair follicles, such as irritation from ingrown hairs or razor bumps, can lead to pathogens infecting them. The infection itself will not cause significant damage to your hair follicles when treated quickly. However, you may experience scarring if your symptoms are severe. Scars can reduce the hair follicles’s ability to support new hair growth.¹ 

How long does folliculitis last?

Most cases of folliculitis do not require treatment and will resolve within a week with proper skin hygiene.² Maintaining good skincare can also stop folliculitis from returning. If you find that your symptoms do not clear up please seek medical assistance. 

What happens if folliculitis is left untreated?

Severe or repeated cases of folliculitis can cause scarring and hair loss.

Summary

Folliculitis is a common skin condition that can cause discomfort. It has multiple causes, ranging from infections to physical irritation. Mild cases usually resolve over a few days, but there are a variety of treatments available for more severe cases. In cases of folliculitis that last for longer than a week or cause a lot of pain, seek advice from your doctor or dermatologist. However, with proper care of your skin and hair follicles, you should be able to prevent the development or the recurrence of folliculitis.