Fungal acne: what it is and how doctors treat it

Fungal acne is a yeast infection of the hair follicles. It makes small bumps that look like acne, which is why it is often treated as acne for months without improving. This guide explains what it is, how it differs from ordinary acne, what causes it, and how a doctor confirms and treats it. It belongs to Skinli's guide to the types of acne.

Skinli is an education site and is not a doctor. Fungal acne needs a doctor to confirm it, because several other conditions look the same. Everything below is meant to help you have that conversation.

What fungal acne is

The medical name is Malassezia folliculitis. It used to be called Pityrosporum folliculitis, and the American Academy of Dermatology (AAD) still uses that older name on its severe acne page, where it calls it an itchy, acne-like rash.

A 2025 review in the Journal of Fungi, a peer-reviewed medical journal, describes it as a common skin condition that is often misdiagnosed. It is caused by an overgrowth of Malassezia, a yeast, inside the hair follicles. Folliculitis means swelling of the hair follicles, the small tubes in the skin that hold each hair.

The word "acne" in the everyday name is misleading. Ordinary acne comes from oil, dead skin cells and bacteria plugging a pore. Fungal acne comes from yeast. That difference is the reason the two need different treatments.

Why the yeast is already on your skin

Malassezia lives on almost everyone. A 2024 case report in Cureus, another peer-reviewed journal, says the yeast is the main fungus on human skin and that it can be found on up to 98 percent of people. The Journal of Fungi review says it is present on the skin of almost all healthy people.

So the problem is overgrowth. The yeast feeds on skin oil, according to the Cureus report, which is why it grows in oily areas like the chest, back and face. Something tips the balance, and the yeast multiplies inside the follicles.

What causes the overgrowth

The Cureus report lists the common triggers:

• Heavy sweating
• Hot climates
• Physical activity
• Recent antibiotics or steroid medicines
• A weak immune system

The Journal of Fungi review adds humidity and skin covered by tight clothing or other material. In one study it cites, 83 percent of 48 patients worked in a warm place, and 71 percent said sweating made it worse. The review says fungal acne is seen most in teenagers and young adults, and more in males than females.

How it differs from ordinary acne

The two can look alike at a glance. The Journal of Fungi review and the Cureus report give the signs that separate them:

Sign	Fungal acne	Ordinary acne
Size and shape	Many small bumps, 1 to 2 millimeters, all alike	Mixed sizes and types
Blackheads and whiteheads	None	Common
Deep nodules or cysts	None	Can occur
Itch	Common: 65 percent of 110 patients in one study	Usually little itch
Where	Upper chest, back, shoulders, face, hairline	Face, chest, back
Response to acne antibiotics	Poor, may get worse	Often helps

The AAD describes ordinary acne as a mix of blackheads, whiteheads, pimples and sometimes deep nodules or cysts. Fungal acne has only the small pimple-like bumps, all looking the same. Doctors call that "monomorphic", meaning one form.

The face is common too. In one study of 49 patients cited in the Journal of Fungi review, the face was the most affected area (57 percent), followed by the back (53 percent) and the chest (37 percent). The review shows bumps on the forehead running into the hairline.

On darker skin, the review says fungal acne may be harder to spot, because dark marks left by the bumps can hide the redness. It suggests paying more attention to itch, bumps that all look the same, and the absence of blackheads and whiteheads.

Why acne treatment often fails

This is the most useful fact for anyone with stubborn, itchy bumps. The Journal of Fungi review says antibiotics taken by mouth, a standard acne treatment, are almost always ineffective for fungal acne. They may make it worse by upsetting the normal balance of germs on the skin and letting the yeast overgrow.

The review cites one study of 110 patients in which 75 percent had first been treated for acne without success. In another, 65 percent of 26 patients had first been diagnosed with acne and given antibiotics or acne treatment. Among patients with a healthy immune system in that study, the average time before the right diagnosis was 61 months.

Steroid creams cause a different problem. The review says they may bring short relief, but the bumps usually return worse when the cream stops, and the cream can change how the bumps look, which makes the diagnosis harder.

If you have used an acne routine steadily for 8 to 12 weeks and your bumps are small, itchy, all alike, and mostly on the chest, back or hairline, that pattern is worth showing to a doctor.

How a doctor confirms it

The Journal of Fungi review says diagnosis starts with what the doctor sees and hears: the look of the bumps, where they are, and whether they itch. Tests then help confirm it:

• Potassium hydroxide test. The doctor scrapes material from the top of a bump and looks at it under a microscope. The review calls this the most accessible and low-cost test.
• Special light. Under a Wood's lamp, an ultraviolet light, fungal acne bumps may glow yellow-green.
• Skin scope. A magnifying tool called a dermatoscope can show signs such as scale around the hair.
• Skin sample. A small biopsy is the most definitive test, the review says, and is used in harder cases.
• Response to treatment. Improvement on antifungal medicine also supports the diagnosis.

The review reports that a 2023 statement from the European Academy of Dermatology and Venereology supports starting treatment based on the doctor's examination alone when a microscope test is not available.

How fungal acne is treated

Treatment targets the yeast. The Journal of Fungi review reports these recommendations from the 2023 European expert statement:

• Healthy immune system: antifungal products applied to the skin are the first choice. The statement names several groups, including azole creams, ciclopirox, propylene glycol, zinc and selenium sulfide.
• Weak immune system: antifungal tablets, such as itraconazole or fluconazole, prescribed by a doctor.

The review says a 2 to 4 week trial aimed at clear improvement is a practical approach, and that most people improve within 2 to 4 weeks of starting antifungal treatment. It says tablets work faster and more reliably in severe or stubborn cases, and that doctors avoid them in people with liver disease or with medicines that interact.

Skinli does not give antifungal doses, because the right product, strength and schedule depend on the doctor's diagnosis. Ask the doctor which product to use, where to apply it, and for how long.

Why it comes back, and how to keep it away

The review says relapse is common. It says long-term maintenance may be needed, such as using an antifungal product less often after the bumps clear, and changing the things that set it off.

Those triggers match the prevention advice the AAD gives for folliculitis in general and for body acne:

• Wear loose clothing in hot, humid weather.
• Change out of sweaty workout clothes and shower soon after exercise.
• Wash your workout clothes after each use.

The review also stresses avoiding antibiotics that are not needed, since they can let the yeast overgrow. Never stop an antibiotic a doctor prescribed without talking to them first.

Other look-alikes

Fungal acne is one of several conditions that look like acne. The AAD says folliculitis from bacteria usually looks like a sudden acne breakout, with a red ring around each spot, and often follows shaving, tight clothing or a hot tub. The Journal of Fungi review says bacterial folliculitis tends to have single pustules that are tender, and that it responds to antibacterial treatment. A doctor sorts these out with the tests above.

Skinli's fungal acne checker compares your bumps with the signs doctors describe and helps you decide whether to ask a doctor about fungal acne. It cannot confirm the diagnosis. For ordinary acne on the same areas, see back acne and chest acne, and for the full daily routine, the complete acne skincare routine. If a new treatment made your skin look worse at first, skin purging vs a real breakout explains what that can mean.