It is a fragrance-free, soap-based acne cleansing foam registered in Korea as a functional cosmetic for acne-prone skin, softened with glycerin, coco-betaine and an amino-acid surfactant, and finished with the Nosca9 heparin-mugwort complex.
A fragrance-free, richly lathering acne cleansing foam with a strong following in Korea, and it earns that for oily skin: it cleans thoroughly and leaves a matte finish. The salicylic acid is modest in effect because it sits in a potassium-soap base and is rinsed away quickly, so treat it as a supportive wash for oily, breakout-prone skin rather than an acne treatment.
Little English-language feedback or US pricing exists for this foam, and the salicylic acid percentage is not published. The assessment relies on the YesStyle ingredient list and the known behaviour of soap-based cleansers containing salicylic acid.
The case for it
Cautions: fungal-acne triggers.
What would change this: A declared concentration would move this to a firmer reading of the dose.
Same rule for everyone. “Good choice” is the verdict on 9,564 of 45,024 concern verdicts across the catalog; rule R2r decided 408 of them. As of September 25, 2026, engine 5.1.1.
Brand or formulator? Disclose a concentration or correct a fact →
The studies behind the evidence row
The case for it
Cautions: fungal-acne triggers.
What would change this: The same active in a leave-on form would be judged on its evidence rather than its contact time.
Same rule for everyone. “Supporting role” is the verdict on 8,197 of 45,024 concern verdicts across the catalog; rule R6 decided 2,017 of them. As of September 25, 2026, engine 5.1.1.
Brand or formulator? Disclose a concentration or correct a fact →
The studies behind the evidence row
The case for it
Cautions: fungal-acne triggers.
What would change this: A declared concentration would move this to a firmer reading of the dose.
Same rule for everyone. “Good choice” is the verdict on 9,564 of 45,024 concern verdicts across the catalog; rule R2r decided 408 of them. As of September 25, 2026, engine 5.1.1.
Brand or formulator? Disclose a concentration or correct a fact →
The studies behind the evidence row
Does the jobDoes what a cleanser is for: surfactant mildness, rinses clean without stripping. Not measured from the label: pH match to skin.
A verdict is DermApproved’s assessment of how well a product’s ingredients fit a concern — never a claim about what the product treats. Evidence dots and collected reviews sit beside it and are never blended in. Rules 0.5.1 · evidence table ev-2026.09-r228 · how we decide
Fation's own store lists this foam as the 2023 winner of Hwahae's acne functional cleansing foam ranking. Hwahae is a widely used Korean app where shoppers rate products and check ingredient lists, so its rankings reflect real enthusiasm from a large, ingredient-aware audience. Popularity is a meaningful signal about how a cleanser feels to use. It is less informative about what the formula does inside a pore, and in the case of the Nosca9 Trouble Cleansing Foam, the two stories are worth separating.
The feel is easy to explain. After water and glycerin come potassium myristate, potassium stearate and potassium palmitate, pre-formed potassium soaps, along with free myristic, stearic and palmitic acids. That combination produces the dense, creamy foam that Korean cleansing foams are known for. Coco-betaine and potassium cocoyl glycinate, a gentler amphoteric and an amino-acid surfactant, soften the soap and keep the lather cushiony, and glycerin sits high enough to take the edge off the squeaky feel. There is no fragrance. For oily skin, it is a satisfying wash: thorough, rich and quick to rinse.
The product is registered in Korea as a functional cosmetic for acne-prone skin, which means its active ingredient, salicylic acid, is recognised by the national regulator for that purpose. Salicylic acid appears mid-list. The chemistry of soap-based cleansers matters here. Soap solutions are alkaline, and in that environment an acid like salicylic acid is partly converted to its salt, salicylate, which penetrates oily pores less readily. Add a contact time of thirty to sixty seconds before rinsing, and the pore-clearing effect is gentle at best. The foam helps keep the skin surface clean and less oily, which is useful, but it does not replace a leave-on treatment.
The rest of the formula is soothing and simple. Sodium heparin, the core of Dong-A Pharmaceutical's Heparin RX Complex, sits near the end with Korean mugwort, panthenol, allantoin and hyaluronic acid. Safflower, papaya, gardenia, apple, Japanese plum and grape extracts contribute small amounts of antioxidants and a mild enzyme story from papaya, though at their level in a rinse-off, the effect is limited.
Who does it suit? Oily and combination skin that likes a rich, matte clean will enjoy it, and acne-prone skin that tolerates soap can use it as the cleansing step in a routine built around leave-on actives such as salicylic acid, azelaic acid, benzoyl peroxide or adapalene. The lack of fragrance is a real advantage. Dry, sensitive, eczema-prone or rosacea-prone skin is a poorer match, because soap bases can disrupt the barrier and leave skin tight, especially alongside drying acne treatments. For those skin types, Fation's own sulfate-free gel or its fragrance-free cleansing water are gentler choices.
There is also an in-brand wrinkle to clear up. Fation sells a Nosca9 Deep Pore Cleansing Foam as well, and the two are sometimes confused. They are different formulas, and both are listed on the brand's Korean store. The Trouble foam is the acne-registered one with salicylic acid; the Deep Pore foam focuses on clays, rice and amino acids.
It helps to think about why a foam like this wins popularity contests. Korean shoppers often favour a dense, whipped lather as a sign of a good cleanser, and many use foaming nets to create a cushion of bubbles that glides over the skin rather than being rubbed in. That technique genuinely reduces friction and makes soap-based foams feel gentler than their chemistry suggests. If you use this foam, a foaming net or a few seconds of whipping in the palms before it touches your face is worth the extra step.
Seasons and climates matter too. In hot, humid weather, when sebum and sweat build up through the day, oily skin often tolerates a soap-based foam twice daily without complaint. In cold, dry months or air-conditioned offices, the same routine can tip combination skin into tightness and flaking, which then makes breakouts harder to manage. Switching to once-daily use in winter, or alternating with a gentler cleanser, keeps the benefits without the dryness.
Availability is the practical obstacle. In North America, the foam is mainly sold through YesStyle, priced in other currencies, and no mainstream US retailer lists a US dollar price. Korean pricing is modest, and a 150 millilitre tube lasts about two months.
A few habits help. Rinse thoroughly, since soap residue dries the skin further. Follow straight away with a hydrating toner and a light moisturiser. If tightness or flaking appears, use the foam only in the evening and rinse with water in the morning. And keep leave-on treatments as the main event.
Fation, launched in 2018 by Dong-A Pharmaceutical, has built the Nosca9 line into one of Korea's better-known acne ranges, and this foam is part of that success. Independent clinical data on the product has not been published.
The verdict balances popularity with chemistry. It is a pleasant, fragrance-free, well-made cleansing foam for oily, breakout-prone skin, and its fans are not wrong about the experience. It is not an acne treatment in a tube, whatever the ranking suggests.
The hero actives that drive this product's performance.
| Ingredient | Function | Evidence |
|---|---|---|
| Salicylic Acid | The acne active behind Korea's functional-cosmetic registration, placed mid-list; in a cleanser built on potassium soaps, part of it converts to salicylate and it is rinsed off quickly, so it acts gently. | Regulator-approved for Acne · emerging certainty |
| Potassium Myristate | Leads the pre-formed potassium soaps (with potassium stearate and palmitate) that give the dense foam and the thorough, oil-removing clean. | Not yet assessed |
| Glycerin | Second on the list, above the soaps, softening the finish so skin feels less tight than with a basic soap foam. | Not yet assessed |
| Potassium Cocoyl Glycinate | An amino-acid surfactant that, with coco-betaine, tempers the harshness of the soap base and keeps the lather creamy. | Not yet assessed |
| Sodium Heparin | The Nosca9 line's soothing Heparin RX Complex, near the end of the list alongside mugwort, panthenol and allantoin. | Not yet assessed |
Ingredient standings describe the active at treatment-level doses and vehicles; this product's own condition grades weigh its actual formula.
Water, Glycerin, Potassium Myristate, Stearic Acid, Potassium Stearate, Glyceryl Stearate, Myristic Acid, Propanediol, Palmitic Acid, Potassium Palmitate, Coco-Betaine, Potassium Cocoyl Glycinate, Hydroxypropyl Starch Phosphate, Butylene Glycol, Salicylic Acid, Sorbitol, Potassium Benzoate, Carthamus Tinctorius Flower Extract, Disodium EDTA, Carica Papaya Fruit Extract, Dextrin, Gardenia Florida Fruit Extract, Pyrus Malus Fruit Extract, Prunus Mume Fruit Extract, Vitis Vinifera Fruit Extract, Calophyllum Inophyllum Seed Oil, Panthenol, 1,2-Hexanediol, Dipropylene Glycol, Allantoin, Hydroxyacetophenone, Hyaluronic Acid, Polyglyceryl-10 Laurate, Sodium Heparin, Artemisia Princeps Leaf Extract
cleanser
AM & PM
Rinse thoroughly, then apply a hydrating toner before any acne treatment; if your skin gets tight, use it only in the evening.
Immediate: a clean, matte, oil-free finish. Short-term (2-4 weeks): less shine and fewer small clogged spots for oily skin. Inflammatory acne still needs leave-on treatment.
The cleansing base consists of pre-formed potassium soaps (potassium myristate, stearate and palmitate) together with free fatty acids, a combination that produces dense, creamy lather. Soap-based cleansers tend to have an alkaline pH, and comparative studies have shown that alkaline cleansers raise skin surface pH, remove more barrier lipids and increase transepidermal water loss compared with milder synthetic detergent cleansers. Coco-betaine and potassium cocoyl glycinate are milder co-surfactants that reduce the overall irritation potential, and glycerin helps limit post-wash dryness.
Salicylic acid is a lipophilic beta hydroxy acid that loosens corneocytes inside follicles. Its activity depends on remaining in its un-ionised acid form, which is favoured at acidic pH. In alkaline soap systems, a portion is converted to salicylate, reducing penetration into sebum-filled follicles, and rinse-off contact limits exposure further. Korean regulations recognise salicylic acid as a functional ingredient for acne-prone skin in rinse-off products; clinical benefit from cleansers is generally modest compared with leave-on formulations.
Sodium heparin, a sulfated glycosaminoglycan used in Dong-A's soothing complex, has anti-inflammatory activity in laboratory studies, though its effect in a rinse-off is uncertain. Artemisia princeps, panthenol and allantoin have soothing and skin-conditioning properties. Carica papaya fruit extract contains papain, a proteolytic enzyme, but its activity in a finished soap cleanser at low levels is unlikely to be significant.
For acne-prone skin, dermatologists usually recommend a gentle cleanser twice daily and rely on leave-on products, such as benzoyl peroxide, salicylic acid, azelaic acid or topical retinoids, for treatment. Medicated cleansers can be helpful for oily skin, but clinicians often note their limited contact time. Soap-based cleansers may be too drying for patients using retinoids or those with sensitive, dry or rosacea-prone skin, in whom syndet or gel cleansers are generally preferred. Fragrance-free products are favoured across these groups. Over-washing and scrubbing are discouraged because irritation can worsen inflammatory acne.
Splash the face with lukewarm water, then whip a pea-sized amount into foam between damp palms. Massage gently over the face for thirty to sixty seconds, focusing on oily areas, then rinse very thoroughly. Follow with a hydrating toner, any acne treatment and a light moisturiser, plus sunscreen in the morning. Oily skin can use it twice daily; if skin feels tight or flaky, use it once a day. On makeup days, cleanse with an oil first.
In Korea, the foam is moderately priced and a 150 ml tube lasts around two months, but in North America it is sold mainly through YesStyle with prices in other currencies, and no US-dollar retail price is available. Its value rests on being a pleasant, fragrance-free cleansing foam for oily skin; the salicylic acid adds less than the acne branding implies. Dong-A Pharmaceutical's backing supports quality, though no independent clinical data exist.
People with oily or combination, breakout-prone skin who enjoy a rich, fragrance-free foam and a matte finish, and who rely on leave-on treatments for acne control.
Dry, sensitive, eczema-prone or rosacea-prone skin is better served by a gentle syndet or gel cleanser. People with fungal acne should avoid the fatty-acid and soap base, and anyone expecting a treatment-strength salicylic acid wash will be disappointed.
Ready to try Fation Nosca9 Trouble Cleansing Foam?
Buy at Amazon ♥A thick white paste that whips into dense, creamy foam.
No added fragrance; a faint neutral soap scent.
A 150 ml white squeeze tube.
Foams richly and rinses to a clean, matte finish. Oily skin usually feels refreshed; drier or reactive skin may feel tight within minutes and flaky after a week of twice-daily use.
About two months of twice-daily use.
spring summer
Fation's official store bills this foam as the 2023 winner of Hwahae's acne functional cleansing foam ranking, a popular Korean ingredient-review app. It sits alongside a newer Deep Pore foam with a different formula.
Fation is a derma-focused Korean skincare brand created by Dong-A Pharmaceutical, a 90-year-old health-science company, and launched in 2018. The brand is young, but its formulas lean on the parent company's pharmaceutical research, and the Nosca9 line is positioned clinically for troubled, sensitive skin.
An acne-registered cleanser treats breakouts on its own.
Rinse-off salicylic acid has limited contact time, especially in a soap base. It supports a routine, but leave-on treatments do the heavy lifting.
The more squeaky your skin feels, the cleaner your pores are.
Squeaky skin reflects lipid removal from the surface. Over-cleansing can worsen irritation and, for some, breakouts.
Yes. It is registered in Korea as an acne functional cosmetic with salicylic acid, though as a rinse-off in a soap base its effect is gentle.
Yes, no fragrance is listed, which is a plus for acne-prone and sensitive skin.
No. The Deep Pore foam is a separate product with a different formula; both are currently sold by Fation.
It is best for oily and combination skin. Its soap base can leave dry skin tight, so a gentler cleanser suits dry types better.
Oily skin can usually use it morning and night. If you notice tightness or flaking, use it once a day.
It contains fatty acids and soap salts that can feed Malassezia, so it is not the best choice for fungal acne.
Recurring themes our editors read across retailer reviews of this product — summaries in our words, not quotations, and not a substitute for your own patch test.
Rich, dense foam
Oily skin feels clean and matte
No perfume
Can feel tight on drier skin
Hard to find outside Korea