Folliculitis: Causes, Treatment and How to Stop It Coming Back

3 days ago

18 min read

Folliculitis is inflammation of the hair follicle caused by infection or irritation. It produces red bumps or pustules about 2–5 millimetres wide that form right at the follicle, without a blocked comedone (blackhead or whitehead). The most common cause is the bacterium Staphylococcus aureus. It can also be caused by Malassezia yeast, hot tub water and shaving, and each cause needs a different type of medicine.

This matters more than most people expect. Many patients arrive with persistent bumps after trying acne products or antibiotics, but the real cause is yeast, which antibacterial medicine does not treat. This article goes through each type of folliculitis, how to tell it from acne, the medicines doctors commonly use, how long treatment lasts, and why some people get it again and again. For other skin conditions, see our overview of all skin condition groups.

What causes folliculitis?

Folliculitis is not a single disease. It is the end point of several different causes that inflame the follicle in the same way. They fall into 3 main groups.

Microorganisms: Staphylococcus aureus bacteria (the most common), Pseudomonas aeruginosa bacteria from hot tub water, gram-negative bacteria after long courses of antibiotics for acne, Malassezia yeast (formerly Pityrosporum), and Demodex mites.
What we do to hair and skin: shaving, waxing, plucking, tight clothing, friction, trapped sweat, and heavy oily products applied over follicles.
Conditions in the body: weakened immunity, poorly controlled diabetes, long-term use of topical or oral steroids, and some medicines such as targeted cancer drugs.

We can usually work out the cause from three things: where the bumps are, what they look like, and what happened in the days before they appeared.

How is folliculitis different from acne?

The most reliable clue is the blocked comedone. If blackheads or whitehead are mixed in, think of acne first. If there are none and the bumps all look alike, think of folliculitis.

Blocked pores: acne has blackheads or whiteheads mixed in. Folliculitis does not.
Appearance of the bumps: acne comes in several stages and sizes in the same area. Folliculitis bumps are usually similar in size, and sometimes a hair can be seen in the middle.
Symptoms: acne is usually tender when pressed. Folliculitis is usually itchy or stinging, especially the yeast type.
Location: acne is most common on the face, chest and upper back. Folliculitis can appear anywhere there is hair, including the legs, buttocks, armpits and groin.
Timing: acne develops gradually with age and hormones. Folliculitis often appears all at once after a clear trigger such as shaving, soaking in a hot tub or heavy sweating.
Response to treatment: if the same bumps look unchanged after 6–8 weeks of ordinary acne treatment, a doctor should review the diagnosis.

The two conditions can occur together, and the appearance can change after some acne medicines, so judging by eye is only a first screen.

Working out your type at home: 4 questions

These questions do not replace an examination, but they help you describe your symptoms to the doctor more accurately.

Itchy or painful: mostly itchy on the back and chest suggests yeast. Deep, painful lumps suggest an abscess.
What happened 1–3 days before: a hot tub soak suggests Pseudomonas. Shaving or waxing suggests irritation and ingrown hairs.
Where it is: under a beard and on legs after shaving is one pattern. The buttocks, from sitting and friction, is another. The back and chest are another.
What you have already used: long-term antibiotics let yeast or gram-negative bacteria take over, and steroid-mixed creams change the look of the bumps and can let a fungal infection spread.

Folliculitis from Staphylococcus aureus bacteria

What it looks like: small pustules 2–5 millimetres wide on a red base, often with a hair in the centre, spread over the scalp, face, neck, chest, back, buttocks and legs. They can rupture and form a yellow crust, and are mildly painful or itchy.

Cause: S. aureus, which lives on the skin and inside the nose of many people, enters the follicle through small scrapes from shaving, sweat or friction.

Severity and urgency: superficial cases are not dangerous and usually improve within 1–2 weeks, but they can progress to a boil if squeezed or if immunity is low.

When to see a doctor: widespread bumps, no improvement after 7–10 days of topical treatment, painful lumps, fever, or red, warm skin around the bumps that is spreading outward.

Hot tub and pool folliculitis (Pseudomonas, hot tub folliculitis)

What it looks like: itchy or painful red bumps or pustules on the trunk, buttocks and thighs where the water reached, often most marked under a swimsuit. It appears about 8–48 hours after soaking, and people who used the same tub may develop it at the same time.

Cause: Pseudomonas aeruginosa, which survives in whirlpool tubs or pools with too little chlorine. Warm water and bubbles make follicles easy for bacteria to enter, and a bath sponge that does not dry out can also harbour the bacteria.

Severity and urgency: in healthy people it usually clears by itself within 7–10 days and needs no antibiotics. Stop using that water and care for the skin according to symptoms.

When to see a doctor: fever, chills, ear or eye pain, deep lumps, no improvement within 2 weeks, or diabetes or weakened immunity. In these cases the doctor may prescribe oral ciprofloxacin, generally 500 milligrams twice a day for about 7 days. Penicillin and cephalexin do not cover this organism.

Folliculitis from Malassezia yeast (Pityrosporum folliculitis)

What it looks like: small bumps of uniform size, about 1–3 millimetres, with no blocked comedone, covering the back, chest, upper arms, neck or hairline. Itching is clearly more prominent than in acne, and it often flares after heavy sweating.

Cause: Malassezia yeast, which lives on everyone's skin, overgrows inside the follicle in hot, humid weather, with heavy sweating, with long-term antibiotics or steroids, or with weakened immunity. This is the type in which antibiotics do not work and may make it worse, because they suppress the bacteria that compete with the yeast.

Severity and urgency: not dangerous, but it rarely clears by itself and often returns in our climate. It needs antifungal medicine, described in the medicine section below. For more on telling the types apart, see yeast acne (fungal acne).

When to see a doctor: itchy bumps on the back and chest lasting more than 2–4 weeks, no improvement with acne medicine or antibiotics, or if you want a KOH skin scraping to confirm the diagnosis before taking oral antifungals.

Folliculitis after long-term acne antibiotics (gram-negative folliculitis)

What it looks like: a person with acne who has taken antibiotics for several months suddenly develops many small pustules around the nose, mouth and chin, or deep lumps, even though the acne had improved.

Cause: antibiotics suppress the normal bacteria on the skin, and gram-negative bacteria such as Klebsiella, Enterobacter or Proteus take their place.

Severity and urgency: not an emergency, but the medicine you are already taking will not help. The approach has to change, and the same antibiotic should not be increased.

When to see a doctor: acne that had improved gets worse while you are on the medicine. The doctor will culture the pustules, and confirmed cases are often considered for oral isotretinoin, about 0.5–1 milligram per kilogram of body weight per day for 4–5 months. This medicine is strictly forbidden in pregnancy and requires blood monitoring.

Bumps from shaving or waxing (pseudofolliculitis barbae)

What it looks like: small red bumps at the follicles 1–3 days after shaving, found under the chin, on the neck, armpits, legs and groin. The hair curls and pierces back into the skin, a hair may be visible under the surface, and dark marks can follow.

Cause: hair cut short and close to the skin grows back into the skin. It is most common in people with curly hair. It does not begin as an infection, but infection can set in on top of it. In Thai, people often lump it together with the rough, goose-skin bumps called khon khut, which is actually a different condition. See how to tell them apart in what causes keratosis pilaris.

Severity and urgency: not dangerous, but it stays chronic as long as you keep shaving close to the skin in the same way. What works is to stop shaving for about 3–4 weeks so the hair grows out beyond the skin, then shave again in the direction of hair growth, leaving the hair about 1 millimetre long.

When to see a doctor: the bumps become pustular or painful, there are dark marks or raised scars, it occurs in a job that requires daily shaving, or you want to consider long-term hair reduction with a laser, which can help because fewer hairs pierce the skin.

Folliculitis on the legs

What it looks like: small red bumps scattered over the shins or thighs, usually linked to shaving, waxing, tight trousers or heavy lotion applied over the skin. The bumps sit at the follicles with a hair visible in the centre.

Cause: mainly irritation from hair removal and friction. Once the skin has small scrapes, S. aureus can get in on top, and scratching makes it worse.

Severity and urgency: mostly not dangerous, and it often improves after 2–4 weeks without hair removal. People often confuse it with keratosis pilaris on the thighs, which is rough like goose skin, usually not itchy, not pustular, and long-standing.

When to see a doctor: bumps that are purple-red spots that do not fade when pressed, which could be vasculitis rather than a follicle problem, as well as a leg that is swollen, red, warm and spreading, fever, or recurrence in someone with diabetes.

Folliculitis on the buttocks

What it looks like: red bumps or pustules on the buttock cheeks, often painful when sitting, with dark marks that last a long time afterwards. People call it buttock acne, but most of the time it is not true acne because blocked comedones are almost never found.

Cause: sweat, long periods of sitting, tight trousers and friction irritate the follicles, and S. aureus infection follows on top. A smaller number are caused by yeast.

Severity and urgency: not dangerous, but it disrupts daily life, and the dark marks can last 3–6 months. For the full breakdown of types, see what causes buttock acne.

When to see a doctor: painful lumps with pus, bumps near the anus, or lumps recurring at the same spot with scars that connect to each other, which may be a different disease that is treated differently.

Folliculitis in the groin

What it looks like: red bumps or pustules along the hair line in the groin and pubic area, usually after shaving or waxing, and painful when rubbing against underwear.

Cause: this area is damp and constantly rubbing, so it meets irritation after hair removal, S. aureus, and ringworm (jock itch) fungus that has gone deep into the follicle, especially after using steroid-mixed creams.

Severity and urgency: superficial cases are not dangerous, but this area has many look-alike conditions, so do not guess. Examples are genital herpes, which usually causes clear blisters in a group and burns badly, molluscum contagiosum, and recurrent abscess-like lumps from chronic sweat gland inflammation (Hidradenitis Suppurativa, or HS).

When to see a doctor: blisters or painful sores, a prior risky sexual contact, painful lumps that keep producing pus, or no improvement after 2 weeks of treatment. If the cause is a fungal infection of the follicle, doctors often prescribe an oral antifungal such as terbinafine 250 milligrams once a day for at least 2–4 weeks, because creams do not reach deep enough.

Deep abscesses from follicles (furuncle and carbuncle)

What it looks like: folliculitis that has gone deep and become a red, hot, very painful lump that grows over 1–3 days with pus in the centre. When several follicles merge into a large lump with several heads, it is called a carbuncle.

Cause: S. aureus spreading from the follicle down into the dermis. It is common on the neck, armpits, buttocks and thighs, and the risk is higher with diabetes, weakened immunity and in people who carry the bacteria in the nose.

Severity and urgency: see a doctor within a few days. A small lump may drain by itself with a warm compress for 10–20 minutes, 3–4 times a day, but a soft lump with pus usually needs to be incised and drained, not treated with pills alone. See the steps in abscesses and pus-filled lumps under the skin.

When to see a doctor: a lump larger than about 1 centimetre, severe pain, fever, red streaks spreading from the lump, a lump in the middle of the face or on the nose, or diabetes. Come promptly, and do not squeeze it yourself.

Chronic folliculitis that keeps coming back

What it looks like: pustules or boils return every few months in the same places or in several places, go away for a while on medicine, and then come back.

Cause: commonly S. aureus living in the nose, which about 20–30% of people carry without symptoms, and which travels from the nose to the skin on the hands. Other causes are a wrong starting diagnosis, such as yeast treated with antibiotics, triggers that are still present, or household members carrying the same bacteria.

Severity and urgency: not an emergency, but do not keep buying antibiotics to take on your own, because that increases the chance of resistant bacteria. The doctor's approach is to culture the bacteria to confirm the type and drug resistance, then reduce carriage with 2% mupirocin in the nostrils twice a day for 5 days, together with bathing in 4% chlorhexidine once a day for 5–14 days, avoiding the eyes and ears.

When to see a doctor: several episodes within 1 year, boils as well, diabetes or weakened immunity, or others at home with similar problems. The doctor may then suggest decolonising the whole household at the same time and keeping personal items separate.

Eosinophilic folliculitis and its link with HIV

What it looks like: very itchy red bumps at follicles on the face, neck, scalp and upper trunk, often chronic, with scratching that leaves sores and dark marks, and no improvement on antibiotics or antifungals.

Cause: an inflammation in which eosinophil white blood cells enter the follicle, rather than a direct infection. It occurs in people with HIV whose CD4 count is usually below 250–300 cells per microlitre, and may flare in the first 3–6 months after starting antiretroviral treatment. It is also seen in people on immunosuppressive medicine, and there is a form in people without immune deficiency called Ofuji disease.

Severity and urgency: not life-threatening, but it disturbs sleep a great deal. When it is related to HIV, the main treatment is antiretroviral therapy (ART) together with itch relief using a short course of high-potency topical steroid, such as clobetasol 0.05% twice a day for no more than 2 weeks per course, or UVB light treatment. Ofuji disease usually responds to oral indomethacin.

When to see a doctor: chronic itchy bumps on the face and upper trunk that neither antibiotics nor antifungals help. The doctor will take a biopsy to confirm. Ordinary folliculitis does not mean you have HIV, but if you have had a risk or have never been tested, a blood test is worth doing.

Demodex folliculitis

What it looks like: small red bumps with fine scale on the cheeks, nose and forehead, with rough, dry skin and mild itching or stinging. It often resembles rosacea or acne.

Cause: overgrowth of Demodex mites, which live in the follicles on most people's faces. It is more common after long-term steroid cream on the face and in people with weakened immunity.

Severity and urgency: not dangerous. The doctor confirms it by scraping or pulling the skin to look at the mites under a microscope, and may then prescribe 1% ivermectin cream once a day or 0.75% metronidazole twice a day, then assess the result at about 4–8 weeks.

When to see a doctor: bumps and scale on the face that do not improve with acne or allergy-rash treatment, or that appeared after stopping a steroid cream.

Drug-induced folliculitis

What it looks like: many red bumps of the same size appearing together on the face, chest and back, with no blocked comedones, within about 1–3 weeks of starting a medicine.

Cause: common culprits are oral or injected steroids, targeted cancer drugs of the EGFR inhibitor group, lithium, and isoniazid.

Severity and urgency: usually not dangerous, and it eases when the medicine can be adjusted. Do not stop the medicine yourself, especially cancer drugs and steroids, which are dangerous to stop suddenly.

When to see a doctor: bumps that interfere with daily life during cancer treatment, or a secondary infection. Tell your treating doctor as well as a dermatologist so they can plan together instead of stopping the medicine.

Conditions that look like folliculitis

Acne (Acne vulgaris): has blocked comedones and mixed stages.
Keratosis pilaris: hard, rough, goose-skin bumps on the upper arms and thighs, without pus and with almost no inflammation.
Heat rash (Miliaria): tiny bumps after sweating, which fade quickly once you cool down and do not sit at the follicles.
Herpes: grouped blisters preceded by marked burning, which need antiviral medicine.
Chronic sweat gland inflammation (HS): recurrent painful lumps in the armpits, groin and under the breasts, with tunnels under the skin.
Fungal infection of the follicle (Majocchi granuloma): ring-shaped lumps and bumps after steroid use on a ringworm rash.

What tests does the doctor do to tell the types apart?

For clear superficial bumps with a straightforward cause, doctors can often diagnose from the examination and history. If it is chronic or not responding to medicine, these tests help choose the right medicine instead of trying one thing after another.

KOH skin scraping: takes a few minutes and shows round yeast or fungal threads, confirming the antifungal route.
Gram stain and culture of pus: used when it keeps returning, does not clear on medicine, or drug-resistant bacteria are suspected. Results usually come in 2–3 days.
Checking for mites: scraping or pulling the skin to look under a microscope when Demodex is suspected.
Biopsy: for cases that resist treatment or when the eosinophilic type is suspected.
Blood tests: blood sugar when boils recur, and HIV when there is a risk or symptoms fit the eosinophilic type.

Medicines used when bacteria are the cause

The medicines below are the standard options doctors often choose. Choosing the medicine, the dose and the prescription is the doctor's responsibility, based on the type of organism, how widespread the rash is, drug allergy history and pregnancy.

Benzoyl peroxide 5% wash: wash the affected area, leave on for 2–3 minutes, then rinse off, 1–2 times a day. It does not cause bacterial resistance, so it can serve as a longer-term base than antibiotics. Watch for dry skin and bleached clothing.
Clindamycin 1% topical: twice a day for 7–10 days. Suitable for a small number of bumps.
Mupirocin 2% topical: 2–3 times a day for 7–10 days. Suitable for localised bumps and small wounds.
Cephalexin, oral: 500 milligrams 4 times a day for 7–10 days. Used when the bumps are widespread, deep, or accompanied by a small abscess.
Dicloxacillin, oral: 500 milligrams 4 times a day for 7–10 days. Used in the same situations. Must not be used if you are allergic to penicillin.
Doxycycline, oral: 100 milligrams twice a day for 7–10 days. Considered when you are allergic to the medicines above or MRSA resistance is suspected. Not used in pregnant women and young children.

What shows the medicine is working is that the pustules dry up within 3–7 days and no new bumps appear. If nothing changes after 7–10 days, do not extend or switch the medicine yourself. Come back to be checked for yeast or to have a culture done.

Antifungal medicines when Malassezia yeast is the cause

If the KOH result or the pattern of symptoms fits yeast, the treatment path is completely different from the section above, and unnecessary antibiotics should be stopped. Choosing between topical and oral medicine is the doctor's responsibility, based on how widespread the bumps are and any underlying conditions.

Ketoconazole 2% shampoo or lotion: lather onto wet skin, leave for 5 minutes, then rinse off, once a day or every other day for 2–4 weeks.
Selenium sulfide 2.5% shampoo or lotion: used in a similar way, left on for 5–10 minutes. It may irritate thin skin and should not be used on open wounds.
Ketoconazole 2% cream: apply thinly 1–2 times a day for 2–4 weeks. Suitable for small areas such as the forehead and hairline.
Itraconazole, oral: 200 milligrams once a day after food for 7 days, and in some people extended to 2–3 weeks. Used when the bumps are widespread or topical treatment is not enough. This medicine interacts with many others, such as statin cholesterol medicines, so tell the doctor about every medicine you take.
Fluconazole, oral: 100–200 milligrams once a day for 1–3 weeks. An alternative to itraconazole. Oral antifungals are not suitable in pregnancy, so tell the doctor if you are pregnant.

What decides the result is that itching eases within 1–2 weeks, followed by the bumps gradually flattening. Leftover dark marks fade much more slowly. This yeast is a normal resident of the skin, so it can come back even when treated correctly. Doctors often advise continuing medicated shampoo 1–2 times a week to keep it under control. For more detail on the medicines, read yeast acne: creams, pills and recurrence.

Why doesn't it clear with treatment, or why does it come back?

Wrong medicine for the organism: antibiotics used on yeast, or antifungals used on bacteria.
Steroid-mixed creams: the bumps flatten at first, but the fungus spreads deeper and the bumps return worse when the cream is stopped.
Not finishing the medicine: stopping after 3–4 days once it starts to improve leaves organisms in the follicles.
Original triggers not changed: still shaving the same way, wearing sweaty clothes for long periods, or using the same towel and razor.
Nasal carriage or resistant bacteria: no culture has been done and carriage has not been reduced.
Underlying conditions: poorly controlled diabetes and weakened immunity slow the response to medicine.

What can you do to prevent it coming back?

Prevention can greatly reduce how often it happens, but no method can guarantee it will never happen again, especially the yeast type.

Shower and change clothes soon after sweating. Avoid sitting in wet workout clothes.
Choose breathable clothing that is not tight over areas that have been affected.
Shave after a warm shower, use shaving gel, shave in the direction of hair growth, do not pull the skin taut, and change the blade when it starts to drag.
Do not share razors, towels or bath sponges with others. Wash towels often and dry them fully.
Hot tubs must be kept at a free chlorine level of at least 3 ppm. Shower with soap straight after soaking, and take your swimsuit off to wash it.
Avoid applying oil or heavy lotion over areas that have been affected.
Keep blood sugar within target if you have diabetes.

How many days does folliculitis take to clear, and does it leave marks?

Superficial bumps from S. aureus and irritation mostly flatten within 7–14 days. The Pseudomonas type clears in 7–10 days. The yeast type needs at least 2–4 weeks of medicine, and the eosinophilic type is more chronic than that. Superficial folliculitis usually leaves no scars, but Thai skin often keeps dark marks from the inflammation for 3–6 months. Avoiding sun, using sunscreen and not picking the bumps help them fade faster. Deep abscesses and repeated squeezing are the main causes of permanent scars.

In short

Folliculitis differs from acne in that there is no blocked comedone, and the bumps usually all look alike.
The causes that change treatment are bacteria, yeast, hot tubs, shaving and immune-related conditions.
Bacterial cases need antibacterial medicine and yeast cases need antifungal medicine. If they are swapped, it usually does not improve.
Most superficial bumps flatten within 7–14 days. If there is no improvement within 2 weeks, have a doctor examine it and work out the type.
If it keeps coming back, a culture and a check for nasal carriage should be done. Do not keep taking antibiotics on your own.
See a doctor promptly if there is fever, a painful lump, red warm skin that is spreading, or if you have diabetes.

Frequently asked questions about folliculitis

What medicine is used for folliculitis?

It depends on the organism. For bacterial folliculitis with few bumps, doctors often give 5% benzoyl peroxide wash together with 1% clindamycin or 2% mupirocin applied for 7–10 days. If the bumps are widespread or deep, oral cephalexin for 7–10 days may be given. The yeast type needs antifungal medicine, such as 2% ketoconazole shampoo lathered on and left for 5 minutes for 2–4 weeks, or oral itraconazole as prescribed by the doctor. Choosing the medicine is the doctor's responsibility after the type has been worked out.

What can I use for folliculitis if I haven't seen a doctor yet?

If there are only a few bumps and no fever, start by washing the area with 5% benzoyl peroxide, leave it on for 2–3 minutes, then rinse off, once a day. Stop shaving or waxing, change clothes after sweating, and avoid squeezing the bumps. If the bumps on the back and chest are very itchy, it may be yeast, and you can use 2% ketoconazole shampoo left on for 5 minutes. What you should not use on your own is steroid-mixed creams, because they let fungus spread, or oral antibiotics. If it has not improved after 2 weeks of this care, come in to be examined.

Does folliculitis go away by itself?

Some types do. Superficial bumps from shaving or friction usually settle within 1–2 weeks once the triggers are avoided. Hot tub folliculitis clears by itself in 7–10 days in healthy people. But the yeast type rarely clears alone, and the eosinophilic type is chronic. Deep abscesses also usually need to be drained. Do not wait if there is fever, a painful lump, spreading red skin, diabetes, or no improvement after 2 weeks, because that usually means it is a type that needs medicine aimed at the organism, or that there is a factor that has not been fixed.

Is folliculitis related to HIV?

Most folliculitis has nothing to do with HIV, because it occurs in people generally from bacteria, yeast or shaving. But there is one type called eosinophilic folliculitis that is seen more often in people with HIV at a stage when CD4 is below 250–300 cells per microlitre. It appears as very itchy bumps on the face, neck and upper trunk lasting several weeks, and antibiotics do not help. If you have symptoms like this or have ever had a risk, you should have an HIV blood test, because once the result is known and antiretroviral treatment is started, both the rash and your overall health can be managed properly.

What causes folliculitis in the groin, and is it contagious?

Most cases are caused by shaving or waxing combined with damp conditions, which irritate the follicles and let S. aureus infection follow on top. It is not a sexually transmitted infection. But this area has many look-alike conditions, such as genital herpes, molluscum contagiosum, ringworm fungus in the follicles and chronic sweat gland inflammation, so a doctor should examine it if there are blisters, sores, painful lumps that keep recurring, or a prior risky sexual contact. In the meantime, stop shaving, wear breathable underwear, and do not apply steroid-mixed creams yourself, as they can let the fungus go deeper.

Folliculitis with pus: can I squeeze it?

No, do not squeeze. Squeezing pushes the bacteria deeper, which turns a superficial bump into a boil, spreads the infection, and leaves scars or dark marks, especially on bumps in the middle of the face and on the nose. Small pustules usually dry up by themselves within 3–7 days when washed with 5% benzoyl peroxide and treated as the doctor advises. If it is a painful lump, apply a warm compress for 10–20 minutes, 3–4 times a day. If the lump is soft, larger than about 1 centimetre, comes with fever, or has spreading redness, a doctor should drain it with sterile instruments instead of squeezing it yourself.

The information in this article is general knowledge, not a diagnosis or an individual treatment order. The choice of medicine, dose and duration of treatment is for the doctor to decide. If you are pregnant, breastfeeding or have an underlying condition, consult a doctor before using any medicine.

Written by Dr. Patara Voravutinon, Dermatologist · Last reviewed November 4, 2026