Fungal acne (Malassezia folliculitis): how to tell if it's fungal and what helps

What is fungal acne?

Despite the name, it isn’t acne. DermNet describes Malassezia (also called pityrosporum) folliculitis as an infection of the hair follicle caused by Malassezia yeasts, mainly M. globosa, M. sympodialis and M. restricta. These yeasts are part of everyone’s normal skin flora and only cause disease under certain conditions.

It’s not rare. A Danish review estimated it affects between 1% and 17% of people, depending on the population studied (PMID 33215579).

Is it fungal acne or regular acne?

	Fungal acne (Malassezia folliculitis)	Acne (comedonal or inflammatory)
Itch	Usually itchy	Usually not itchy (can be sore)
Look	Small (1–2 mm) bumps and pustules, all the same size	Mixed sizes and stages
Blackheads/whiteheads	None	Usually present
Where	Upper back, chest, shoulders, forehead and hairline, chin, neck, upper arms	Face, back, chest
Triggers	Heat, humidity, sweating, occlusion, antibiotics, steroids	Hormones, pore-clogging products, genetics
Response to antibiotics	No help; can make it worse	Often helps inflammatory acne
Response to antifungals	Improves	No effect

Sources: DermNet, Rubenstein & Malerich 2014, Prindaville et al. 2018.

A few details worth knowing:

• Itch is common but not universal. About 80% of patients reported itching in one study cited by Rubenstein & Malerich, and 65% in a review of 110 patients aged up to 21. “It doesn’t itch” makes fungal acne less likely, not impossible.
• The face is common, not just the back. In that same 110-patient review, lesions typically involved the forehead extending into the hairline, plus the upper back. In another study, the face was the most common site.
• Antibiotics are a big clue. DermNet lists antibiotic use as a risk factor. In the 110-patient review, more than three-quarters of patients also had acne that had recently been treated with antibiotics.
• Both can happen together. That’s a major reason it gets missed.

Skin Realist check: Reddit threads often decide “looks fungal” from a photo. Nobody can reliably diagnose it from a photo, including dermatologists: the Danish review notes it’s clinically hard to distinguish from acne and needs microscopy or biopsy to confirm.

If your bumps are on your forehead, see our side-by-side comparison of closed comedones, fungal acne and keratosis pilaris.

What causes fungal acne?

Malassezia yeasts feed on skin oils, and they live on most people without causing trouble (PMID 36741270). DermNet lists the conditions that tip things over:

• hot, humid climate
• high oil (sebum) production
• heavy sweating
• occlusion from heavy creams (emollients) or sunscreens
• antibiotic use
• a weakened immune system, including steroid creams or tablets

Rubenstein & Malerich add summer heat, intense exercise, occlusive clothing and products such as makeup, lotions and sunscreens as triggers. Which ingredients are a problem is much less clear than online “fungal-acne-safe” lists suggest; see fungal acne ingredients.

How do dermatologists diagnose fungal acne?

DermNet explains the diagnosis is usually suspected from how the skin looks, then confirmed in the lab:

• Skin scraping (KOH preparation): a sample is examined under a microscope for yeast. Rubenstein & Malerich note that because Malassezia is normal skin flora in most healthy people, seeing it on a surface scraping isn’t proof on its own; sampling from inside the follicle is more reliable.
• Wood’s lamp: an ultraviolet light that may make affected follicles glow yellow-green.
• Skin biopsy: shows yeast inside the follicle, used when the diagnosis is unclear.

What to bring to the appointment: photos from when it was worst, a list of everything you put on your skin and hair, and what you’ve already tried and for how long. Tell them about any recent antibiotics.

How is fungal acne treated?

What doctors use

• Topical antifungals. DermNet lists selenium sulfide shampoo, econazole and topical ketoconazole, and says they work in most cases, though they may need longer courses than tablets. In the 110-patient review, ketoconazole shampoo was the most common treatment and improved or cleared most cases.
• Oral antifungals. Rubenstein & Malerich describe oral antifungals as the most effective option, especially at first, because the yeast sits deep in the follicle. DermNet says trial results are inconsistent. These are prescription medicines with possible side effects, so they’re a decision for your doctor.
• Fixing the triggers. DermNet puts this first, because otherwise it tends to come back.

One study cited by Rubenstein & Malerich found topical ketoconazole alone cured only 12% of 26 patients. So topical treatment helps many people, but it doesn’t work for everyone.

Antifungal shampoo “masks”: what people try

On Reddit, the most common home approach is using an anti-dandruff shampoo on the face as a short mask. The two shampoo actives people use are:

• zinc pyrithione 1%, the active in many anti-dandruff shampoos. Lab research shows it acts against Malassezia in several ways, including reducing the yeast’s lipase enzymes (Park et al. 2018).
• ketoconazole, sold OTC in the US as Nizoral A-D, and at 2% by prescription.

Be clear about what’s label-supported and what isn’t:

• The OTC labels are for dandruff, as whole-head washes. The Nizoral A-D label directs lathering into wet hair, rinsing, repeating, and using every 3–4 days for up to 8 weeks for adults and children 12 and over. Zinc pyrithione shampoo labels direct massaging into the scalp and rinsing, at least twice a week. Neither directs leaving it on your face.
• A prescription 2% ketoconazole shampoo label we checked directs applying it to damp affected skin, lathering, leaving it on for 5 minutes and rinsing. That’s for the conditions a doctor prescribes it for.
• The “few seconds to a few minutes on the forehead, every couple of days” method is a folk practice. It may help some people, but it isn’t tested or label-directed.

If you try it:

• keep it well away from your eyes (people in these threads report it stings badly)
• start with short contact, and stop if your skin burns or gets raw
• don’t combine it with several other new actives at once, so you can tell what’s working
• if there’s no clear improvement after a few weeks, see a doctor instead of escalating contact time

Skin Realist check: if an antifungal shampoo clears your bumps quickly, that’s a strong hint they were fungal, but it’s still not a diagnosis. If it does nothing, they may be closed comedones or KP, which need different treatment.

How do you stop fungal acne coming back?

DermNet says recurrence is common even after successful treatment. It suggests:

• reviewing and reducing triggers: sweat, heat, tight or occlusive clothing, heavy creams
• for people who get it repeatedly, a topical antifungal used regularly (weekly use can help prevent recurrence)

Practical steps that follow from the known triggers: shower soon after sweating, change out of damp workout clothes, choose lighter moisturisers and sunscreens, and tell any doctor prescribing antibiotics that you’ve had fungal folliculitis. Rubenstein & Malerich specifically advise avoiding antibiotics where possible, because they can disturb skin flora and encourage yeast overgrowth.

What about other treatments people mention?

• Cutting back skincare and makeup. Because DermNet lists occlusion from emollients and sunscreens as a risk factor, simplifying to fewer, lighter products is sensible. There’s no evidence for a specific number of products to cut.
• Hypochlorous acid spray. Some preliminary studies report benefits in ordinary acne, but the evidence is early, and we found nothing on fungal acne specifically.
• “FA-safe” product lists. These are built on assumptions that the research only partly supports. See fungal acne ingredients.

When should you see a dermatologist?

• You suspect fungal acne and want a proper diagnosis
• Bumps keep coming back after antifungal shampoo, or didn’t improve after a few weeks
• It’s widespread, very itchy, or you have a weakened immune system
• You’ve been on antibiotics for acne and it’s getting worse