Keratosis pilaris is the patch of small rough bumps on the upper arms, thighs and cheeks that most people know as chicken skin. It is harmless, it is not an infection or an allergy, and it can be smoothed considerably if the texture bothers you.
The same eight facts on every condition comparison.
It is a yeast-driven follicle eruption.
Malassezia, which normally lives on skin, can multiply inside follicles.
It has a typical pattern.
Small itchy bumps cluster on the upper trunk, shoulders, neck or hairline.
The nickname misleads.
Conventional acne treatments may not address the yeast.
It can coexist with acne.
Blackheads, whiteheads and mixed lesion sizes point to acne vulgaris as well.
Overview
Also called Malassezia folliculitis: inflammation around hair follicles linked to yeast. It often produces small, similar-looking, itchy bumps rather than blocked pores.
It causes rough bumps.
Small plugs form around hair follicles.
It has typical sites.
It often affects the upper arms and thighs, and sometimes the cheeks.
It is not acne.
It is not caused by dirt.
Inflammation is a different issue.
Pain, pustules, scarring or an unusual pattern suggest another condition.
Uniform bumps Small bumps all the same size.
Upper back A common site.
Forehead Clusters along the hairline.
Classic keratosis pilaris Rough skin-colored bumps.
Red keratosis pilaris Bumps with redness around them.
Facial keratosis pilaris Redness and bumps on the cheeks.
Malassezia yeast can overgrow inside hair follicles and trigger inflammation. This produces similar-looking itchy bumps and differs from the plugged pores that form blackheads and whiteheads.
Keratin builds up at the openings of small hair follicles. These plugs create rough bumps, sometimes with surrounding inflammation or darker marks.
Fungal Acne. Fungal Acne Often teens and young adults Malassezia folliculitis is more common in adolescents and young adults, but it can occur at other ages. A new rash after heat, sweating, antibiotics or immune suppression can be a useful clue; timing cannot confirm the diagnosis.
Keratosis Pilaris. Often begins in childhood and becomes more noticeable during adolescence.
Fungal acne is caused by an overgrowth of Malassezia yeast inside hair follicles. The yeast normally lives on skin but grows too much in warm, oily, sweaty conditions.
An overgrowth of normally present Malassezia yeast within follicles, followed by inflammation. Malassezia normally lives on skin. Finding surface yeast or noticing itch alone does not confirm that it is causing the rash.
Keratosis pilaris happens when keratin, a skin protein, builds up and plugs hair follicles. Each plug forms a small rough bump.
This is not usually considered an inherited disorder. Oily skin and other individual factors can influence susceptibility.
It runs strongly in families and is often inherited from one parent.
Evidence labels come from each condition’s own treatment list.
The main over-the-counter treatment, used as a body wash rather than for hair. Lather it over the chest, back, shoulders and hairline in the shower and leave it on several minutes before rinsing, daily for two to four weeks. Rinsing it straight off is the most common reason it seems not to work.
An anti-dandruff shampoo used the same way, lathered on the affected areas and left several minutes. A reasonable alternative if ketoconazole irritates or is hard to find. It can be drying and can discolor light-colored hair, so keep it on the body.
The gentlest of the three anti-dandruff washes, and the easiest to keep using long term. It is a good choice for maintenance once the bumps have cleared, once or twice a week through the hot months. It is usually a little weaker than ketoconazole for clearing an active crop.
A sulfur wash or soap has some activity against this yeast and is an option if the antifungal shampoos are not tolerated. The evidence in fungal acne specifically is thin. It smells and can be drying on the chest and back.
It has some effect on Malassezia, which is why a few people improve partially on it and then stall. It is not the right tool here, and used as a wash it can leave the chest and back dry and irritated. If it half-works, that is a hint to switch to an antifungal wash rather than to use more of it.
It works by clearing blocked pores, and this is not a blocked-pore condition, so it does not act on the yeast. Some people find a wash mildly helpful for the texture. It will not clear the bumps, and scrubs and brushes usually make an irritated chest and back angrier.
Widely suggested online for fungal acne and not well studied in it. It irritates inflamed skin easily, and it is a common cause of allergic reactions on the chest and back. A proven antifungal wash costs about the same and is available without a prescription.
Oil-soluble, so it gets down inside the follicle and works on the plug from within rather than at the surface. Useful when the bumps are the main complaint and urea has not been enough. It is drying, so it needs pairing with a moisturizer, and it is not the one to reach for on a child's cheeks.
Friction cannot reach a plug sitting inside the follicle, so scrubbing removes surface skin without touching the cause. It adds redness, and on deeper skin tones it leaves dark marks that outlast the bumps by months. A soft washcloth used gently while washing is as far as this should go.
The single most useful thing for keratosis pilaris, because it does both jobs at once: it holds water in the dry skin and it breaks down the keratin plug. Use 10 to 20 percent on the arms or thighs most days, on damp skin after a shower. It stings a little on cracked skin, and the bumps return within a few weeks of stopping.
Ammonium lactate or lactic acid lotion at around 12 percent does the same two jobs as urea, slightly more gently, and it is often the easier one to keep using daily. Good first choice if urea stings. Like everything here, it manages the bumps rather than ending them.
Loosens the dead cells stuck at the surface, which smooths the skin around the bumps. It is the most likely of the acids to sting and to leave the skin pink, so it suits the arms and thighs better than the cheeks. On deeper skin tones, build up slowly, because irritation is what leaves the dark marks.
Changes how the follicle sheds its cells, so fewer plugs form in the first place. It is slower than the acids and more irritating, so it is usually a second step rather than a first one. Start two nights a week on one arm, and always put a moisturizer over it.
It moisturizes, and moisture genuinely softens the texture a little, so it is not useless. It cannot dissolve a keratin plug, so it will not clear the bumps, and the widely shared claim that it cures keratosis pilaris is not supported. If you like it, use it as the moisturizer over an acid cream rather than instead of one.
Ketoconazole 2% cream. The prescription strength, used as a cream on limited areas such as the jawline, forehead or hairline, or as a shampoo on the body. It is the usual next step when the over-the-counter 1% wash has not been enough. A cream is impractical for a whole back, which is where the wash or tablets take over.
Clotrimazole cream. An older antifungal cream, applied twice a day to small patches. It works against this yeast and is inexpensive and widely available. Like any cream, it only suits areas you can realistically cover, so it is a jawline and hairline option rather than a chest and back one.
Ciclopirox cream or shampoo. Another antifungal option, used when ketoconazole has irritated the skin or has not worked. There is less published evidence in Malassezia folliculitis specifically than for ketoconazole. It is used the same way, with the shampoo left on for several minutes.
A retinoid works on blocked pores, and there is no plug to clear here, so it does not treat the yeast. It is often already in use because the bumps were assumed to be acne. It can stay if you also have genuine acne, but it is not what clears this.
A topical antibiotic reduces the bacteria that compete with the yeast, so at best it does nothing here and at worst the bumps get denser. Skin that gets worse rather than better on an acne antibiotic is one of the strongest clues that this is fungal acne.
The prescription version of the retinoid idea: it normalizes how the follicle sheds, so plugs form more slowly. It is used when over-the-counter acids have not been enough after six weeks. It is drying and irritating on arms and thighs, so it is introduced two or three nights a week, and it makes the skin more sun-sensitive.
A stronger retinoid cream, occasionally used on stubborn arms when tretinoin has not worked. It is more effective on the plugs and also more irritating, which is the trade-off. It is not used in pregnancy — ask your doctor before starting it if that applies to you.
A mild steroid cream used in short courses when the red halo around the bumps is the main complaint, not the roughness. It calms the inflammation for a while and does nothing to the plugs. It is not a long-term answer, because weeks of steroid on thin skin like the cheeks causes its own problems.
The tablet most often used for stubborn or widespread cases, usually for one to three weeks. It clears extensive chest and back involvement far more reliably than a wash can. It interacts with a long list of other medicines, so the prescriber checks what else you take first.
The other antifungal tablet used here, often as a weekly dose for a few weeks. It suits people who cannot take itraconazole. Tablets clear the yeast but do not change the heat, sweat and occlusion that brought it on, so a maintenance wash is usually continued afterwards.
The antifungal tablet used for nail and foot infections, and it is a poor choice here. Malassezia is not reliably killed by it at the doses used by mouth. If an antifungal tablet is being considered, itraconazole or fluconazole are the ones with evidence in this condition.
An antibiotic prescribed for acne is one of the most reliable ways to make this worse, because it clears the bacteria that hold the yeast in check. A crop of itchy bumps appearing a few weeks into or after a course is a classic history. It is not a treatment for fungal acne.
Aimed at the redness rather than the texture, so it is for the variant where the background color bothers you more than the bumps. Several sessions are usually needed and the bumps themselves are left much as they were. On deeper skin tones it is less useful and carries more risk of pigment change, so it is not usually the first suggestion.
Removing the hair takes away the thing that gets trapped under the plug, and small studies show the bumps and roughness improve with it. It is expensive for a harmless condition, which is why it is rarely the first plan. It makes most sense for someone already having the area treated for hair.
A stronger version of the acid creams, applied in a clinic to the arms or cheeks. It can smooth the texture for a while, and the effect fades in the same way, so the daily cream is still needed afterwards. It is an add-on for people who want a faster start, not a replacement for the routine.
Sanding the surface has the same problem as a body scrub: the plug sits inside the follicle, below where it reaches. Any smoothness is short-lived, and it adds redness. On deeper skin tones the irritation can leave dark marks, so it is one to skip.
Fungal acne appears over a short period rather than gradually, and the right treatment works quickly. It comes back if the conditions return.
Keratosis pilaris has a season. Cold, dry months and indoor heating make it rougher and more visible, and humid summers often flatten it without treatment. People often credit a product for a change the weather made. Underneath that, it follows a slow arc from childhood.
The bumps multiply but stay small
They stay small rather than growing. The itch bothers most people more than the bumps.
Keratosis pilaris often accompanies dry skin or an eczema tendency. Some variants leave persistent redness, pigment change or, less commonly, localised scarring.
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Seek help for a persistent itchy, uniform rash, repeated relapses, or bumps that have not improved with acne treatment. A skin sample may help distinguish causes.
Fever, spreading painful redness, or rapidly worsening bumps need prompt assessment, especially if your immune system is suppressed.
Seek assessment if bumps are painful, very inflamed or unlike the usual rough follicular pattern. Gentle treatment can reduce roughness without scrubbing.
Three things separate them. Fungal acne itches; acne usually does not. Fungal acne has no blackheads or whiteheads. And the bumps are all the same small size, in a sheet across the chest, shoulders, upper back and hairline, not a mix of sizes on the face. A start after antibiotics, steroids or a hot sweaty stretch adds to the case.
Yes, often. Many people have ordinary acne on the face and Malassezia folliculitis on the chest and back, treated in parallel. A routine aimed only at acne leaves half the problem untouched.
No. The yeast already lives on almost everyone's skin. Nobody gave it to you and you cannot pass it on.
The idea rests on something real — this yeast cannot make its own fats and takes them from its surroundings. But the ingredient lists online are more confident than the evidence. Avoid heavy oils, butters and occlusive products on the affected areas while it is active, and treat the yeast directly rather than rebuilding a routine.
Because the conditions return — heat, sweat and occlusion, usually every summer. That is not treatment failure. Most people who stay clear use the antifungal wash once or twice a week through the warm months.
Scars are uncommon. Flat dark marks are very common, and because the bumps arrive in large numbers they cover a wide area and take months to fade, particularly on deeper skin tones. Not scratching and treating early reduce them most, and daily sunscreen helps them fade faster.
For most people it fades substantially through the twenties and thirties with nothing done. A minority keep it for life. Treatment does not speed that up, it keeps the skin smooth meanwhile.
The tendency to plug the follicle is genetic, and the cream only clears plugs that have already formed. Within a few weeks of stopping, new ones build. That is the condition behaving normally, not the product failing.
No. No food causes it and no diet clears it. It is inherited and tied to dry skin, not nutrition. The vitamin deficiency story is a myth.
Not with friction. The plug sits inside the follicle where a scrub cannot reach, and scrubbing adds redness and, on deeper skin tones, dark marks. Urea, lactic acid and salicylic acid do reach it.
Cold air outside and heated air inside both dry the skin, and dry skin plugs its follicles more readily. Most people find it flattens in humid summer months. Shorter, cooler showers and daily moisturizer take the edge off.
That is keratosis pilaris rubra, the same condition with more inflammation around each follicle. Creams help the texture more than the redness, so if redness is your main complaint see a dermatologist, who has options aimed at it.
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