Red Serum Plus
Medicube Red Serum Plus is a Korean-market serum built around Salicylic Acid, formulated in Korea and sold here in its original Korean-market formula rather than a US-shelf reformulation.
No reviews yet55ml
$45.44 per 100 ml
- Korean-market formula
- Ships from California or direct from Korea
- Korean barcode and batch code intact
- Suited to
- normal skincombination skindry skin
- Helps with
- general upkeep alongside the rest of a routinea Korean-market alternative to a comparable US productsteady, repeated use rather than a single application
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- 30-day returns
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- Tracked delivery to your door
Key benefits
- Built around Salicylic Acid, positioned for pore care.
- Built around Melaleuca Alternifolia (Tea Tree) Leaf Oil, positioned for clarity.
- Built around Centella Asiatica Extract, positioned for comfort.
- Formulated as a serum for the treatment step right after toner.
- The Korean-market Medicube formula for Red Serum Plus, matching what Medicube sells in Korea rather than a US-reformulated line.
Key actives
19Salicylic AcidPore care
Salicylic Acid sits in the middle stretch of the ingredient list, a supporting rather than a headline role. It is an ingredient chosen for pore care: a BHA that works inside the pore lining, included at a level meant for regular use on textured, congestion-prone skin.
25Melaleuca Alternifolia (Tea Tree) Leaf OilClarity
Melaleuca Alternifolia (Tea Tree) Leaf Oil sits in the middle stretch of the ingredient list, a supporting rather than a headline role. It is an ingredient chosen for clarity: a botanical long used in blemish-prone routines for its fresh, clean feel on the skin's surface.
31GlycerinFormula base
Glycerin sits in the middle stretch of the ingredient list, a supporting rather than a headline role. It is a texture ingredient rather than a headline active: a classic humectant that pulls moisture to the skin's surface and keeps the rest of the formula feeling comfortable rather than drying.
32PropanediolFormula base
Propanediol sits in the middle stretch of the ingredient list, a supporting rather than a headline role. It is a texture ingredient rather than a headline active: a plant-derived solvent and humectant that helps the other ingredients dissolve evenly and gives the formula a lighter, less sticky finish.
36Centella Asiatica ExtractComfort
Centella Asiatica Extract sits further down the ingredient list, in a supporting, lower-weighted role. It is an ingredient chosen for comfort: a cica extract long used in Korean formulation for its calming reputation, chosen here to keep the finish comfortable on skin that flares easily.
Inside the formula
Inside the formula
- 19Salicylic Acid
- 25Melaleuca Alternifolia
- 31Glycerin
- 36Centella Asiatica
Where each key active sits on the declared ingredient list, by entry number. Position is proportion: the further forward, the larger its share.
Medicube Red Serum Plus
What does the Red Serum Plus actually contain?
Its ingredient list is led by Salicylic Acid, with the rest of the formula built to support that active rather than compete with it. We list the ingredients in the order the manufacturer prints them, so the ones near the top of the panel are doing the most work in the formula.
How do I use the Red Serum Plus?
Use this serum as the treatment step right after toner. To apply, smooth or press onto cleansed, toned skin and follow with moisturizer. Keep it to AM/PM unless the packaging states otherwise, and give the rest of the routine a moment to settle before layering the next step. Give it a full bottle or box before judging the result, since most Korean routines are built for steady use rather than a single application.
Is the Red Serum Plus the same formula sold in Korea, or a US version?
This Red Serum Plus is the Korean-market formula, not a version reformulated for US shelves. It arrives with its original Korean-market barcode and batch code intact so the formula can be checked against the box on arrival.
Can I use the Red Serum Plus with other actives in my routine?
Yes, as long as it is used in its own step, the treatment step right after toner, and not layered on top of a product doing the same job. Introduce any new step gradually over the first week or two and keep an eye on how the skin responds before adding a second new active alongside it.
Who is the Red Serum Plus suited for?
It suits most skin types looking for treatment step right after toner rather than a single acute problem. It comes in a 55ml format. Anyone with a known sensitivity to a specific ingredient should check the full ingredient panel on this page before buying.
Not on the ingredient list below: silicones, parabens, sulfate surfactants, mineral oil or petrolatum and added color.
Full INCI (59): Water, Dipropylene Glycol, Xylitol, Propylene Glycol, Alcohol, Sorbitol, PEG/PPG-17/6 Copolymer, Dimethicone/Vinyl Dimethicone Crosspolymer, Diethoxyethyl Succinate, Portulaca Oleracea Extract, PEG-60 Hydrogenated Castor Oil, Polyacrylamide, Betaine, Butylene Glycol, Phenoxyethanol, C13-14 Isoparaffin, Triethanolamine, Dipotassium Glycyrrhizate, Salicylic Acid, C12-14 Pareth-12, Carbomer, Colloidal Sulfur, Tocopheryl Acetate, Laureth-7, Melaleuca Alternifolia (Tea Tree) Leaf Oil, Zanthoxylum Piperitum Fruit Extract, Pulsatilla Koreana Extract, Usnea Barbata (Lichen) Extract, Dinatrium Ethylendiaminetetracetic Acid, Fragrance, Glycerin, Propanediol, Zingiber Officinale (Ginger) Root Extract, Platycodon Grandiflorum Root Extract, Camellia Japonica Leaf Extract, Centella Asiatica Extract, Polygala Tenuifolia Root Extract, Willow Bark Extract, Phellodendron Amurense Bark Extract, Citrus Paradisi (Grapefruit) Seed Extract, Magnolia Officinalis Bark Extract, Rhus Semialata Gall Extract, Camellia Sinensis Leaf Extract, Taraxacum Officinale Dandelion Rhizome/Root Extract, Oryza Sativa (Rice) Extract, Benzyl Alcohol, Lavandula Angustifolia (Lavender) Water, Borago Officinalis Extract, Artemisia Vulgaris Extract, Chamomilla Recutita (Matricaria) Flower/Leaf Extract, Salvia Sclarea (Clary) Extract, Hyacinthus Orientalis (Hyacinth) Extract, Centaurea Cyanus Flower Extract, Tocopherol, Ovalicin, Blue 1 (Ci 42090), Sophora Angustifolia Root Extract, Melia Azadirachta Extract, Citrus Paradisi (Grapefruit) Fruit Extract
Ingredient list read from inkeedecoder.com on 30 August 2026.
53 of 59 explained
- Water solvent
- Water is the base almost every serum, toner and cream is built on. It dissolves the water-loving ingredients and sets how light the finished texture feels. On an INCI list it is usually first, which only means it is the largest single ingredient by weight.
- Dipropylene Glycol humectant
- Dipropylene Glycol is a glycol used as a solvent and a light humectant. Its main job is keeping the rest of the formula dissolved and the texture fluid rather than adding hydration of its own.
- Xylitol humectant
- Xylitol is a sugar alcohol humectant. It holds water in the outer layer of skin and is often paired with anhydroxylitol and xylitylglucoside as a hydration trio.
- Propylene Glycol humectant
- Propylene Glycol is a small glycol used as a humectant and solvent. It hydrates and helps actives dissolve; newer formulas often swap it for propanediol, which does the same job with a lighter feel.
- Alcohol solvent
- Alcohol here means ethanol. It dissolves ingredients water cannot, evaporates fast so a formula sets quickly and does not feel heavy, and thins texture. In quantity it can leave dry or reactive skin feeling tight, which is why many Korean formulas avoid it and some deliberately use it for a fast, weightless finish.
- Sorbitol humectant
- Sorbitol is a sugar alcohol used as a humectant. It hydrates like glycerin with a smoother, less sticky finish, and it adds a little body to watery textures.
- PEG/PPG-17/6 Copolymer solvent
- PEG/PPG-17/6 Copolymer is a water-soluble polymer used as a humectant and solubiliser. It keeps a formula fluid and helps oils stay dispersed.
- Dimethicone/Vinyl Dimethicone Crosspolymer silicone
- This is a silicone elastomer, a soft springy gel. It fills the look of fine texture and gives the velvety, blurred finish of a primer.
- Diethoxyethyl Succinate solvent
- Diethoxyethyl Succinate is a solvent that helps water-resistant actives spread and sink in evenly. It also leaves a light, silky feel.
- Portulaca Oleracea Extract plant extract
- Portulaca Oleracea is purslane. Its extract is unusually high in omega-3 fatty acids and antioxidants for a plant, and Korean formulas use it for the look of reddened, reactive skin.
- PEG-60 Hydrogenated Castor Oil emulsifier
- PEG-60 Hydrogenated Castor Oil is a castor-oil-derived solubiliser. It is what keeps fragrance and oil-soluble ingredients dissolved in a watery formula so it stays clear.
- Polyacrylamide film former
- A polymer used to thicken and to hold an emulsion together. It leaves a light film that helps a formula stay put.
41 more explained
- Betaine humectant
- Betaine is a sugar-beet-derived humectant that cells use to hold water. In a formula it hydrates and takes the edge off cleansers and acids, which is why it often appears alongside them.
- Butylene Glycol humectant
- Butylene Glycol is a small glycol that does two jobs at once: it holds water in the top layer of skin and it dissolves plant extracts and actives that plain water cannot. It also thins a formula, which is why watery Korean essences lean on it.
- Phenoxyethanol preservative
- Phenoxyethanol is the most widely used cosmetic preservative outside the paraben family. It keeps a water-containing formula from growing bacteria and mould, and is capped at one percent in most markets, so it always sits low on a list.
- C13-14 Isoparaffin emollient
- A light branched hydrocarbon, usually part of the thickener system in a lotion. It gives a smooth, quick-spreading feel.
- Triethanolamine pH adjuster
- Triethanolamine is an alkaline base used to neutralise acidic gelling agents such as carbomer. Once neutralised the gel thickens, which is what holds a clear gel together.
- Dipotassium Glycyrrhizate active
- Dipotassium Glycyrrhizate is a water-soluble salt derived from licorice root. It is the licorice fraction Korean formulas use for the look of redness, and it is far more stable in water than the whole extract.
- Salicylic Acid exfoliant
- Salicylic Acid is a BHA, and the only common exfoliant that is oil soluble, so it can work inside a pore rather than only on the surface. It loosens the dead cells that block pores and is used for the look of congested, oily skin.
- C12-14 Pareth-12 emulsifier
- C12-14 Pareth-12 is a solubiliser that keeps oils and fragrance in solution so a clear formula stays clear.
- Carbomer thickener
- Carbomer is a synthetic polymer that only gels once a base neutralises it, which is why arginine or tromethamine sits nearby on the list. It gives the clear, non-stringy gel texture a xanthan formula cannot reach.
- Colloidal Sulfur active
- Colloidal Sulfur is elemental sulfur milled fine enough to disperse in water. It is used in masks and spot products for the look of congested, oily skin, and it carries its own faint sulphur smell.
- Tocopheryl Acetate antioxidant
- Tocopheryl Acetate is a stable vitamin E ester that skin converts to tocopherol. It is used as an antioxidant and a light emollient and holds up better than plain vitamin E in a formula.
- Laureth-7 emulsifier
- Laureth-7 is a mild emulsifier and wetting agent. It helps oils and water mix and improves how evenly a formula spreads.
- Melaleuca Alternifolia (Tea Tree) Leaf Oil fragrance component
- Tea Tree Leaf Oil is an essential oil from an Australian shrub, carrying terpinen-4-ol. Korean formulas use it in products aimed at blemish-prone skin; it is potent, aromatic, and one of the essential oils most likely to bother reactive skin.
- Zanthoxylum Piperitum Fruit Extract plant extract
- Zanthoxylum Piperitum is Korean pepper. Its fruit extract is used as a conditioning plant extract and is often paired with pulsatilla and usnea in Korean formulas.
- Pulsatilla Koreana Extract plant extract
- Korean pasque flower extract, a native anemone relative. It is used as a conditioning plant extract, usually beside other Korean herbal extracts.
- Usnea Barbata (Lichen) Extract plant extract
- Beard lichen extract, carrying usnic acid. It resists microbes, so formulas use it both as a plant extract and as part of a preservative system.
- Dinatrium Ethylendiaminetetracetic Acid chelator
- EDTA is a chelator: it locks up trace metal ions from water and packaging that would otherwise turn a formula cloudy, off-colour or rancid. It does nothing to skin and appears at a fraction of a percent.
- Fragrance fragrance
- Fragrance, or Parfum, is a single declaration standing for a whole scent blend, which can be dozens of materials. Regulators allow it as a trade secret, so a list showing only this word does not say what the scent is made of. It is the most common trigger named by people with reactive skin.
- Glycerin humectant
- Glycerin is the most used humectant in skincare. It draws water into the outer layer of skin and holds it there, and it is one of the very few ingredients whose hydrating effect is settled science rather than marketing. Higher amounts feel tacky, which is why it is usually blended.
- Propanediol humectant
- Propanediol is a plant-derived glycol used in place of propylene glycol. It hydrates, carries actives into solution, and gives a lighter, less sticky slip than glycerin at the same strength.
- Zingiber Officinale (Ginger) Root Extract plant extract
- Ginger root extract. It carries gingerols, gives a warming sensory character, and is used as an antioxidant-rich herbal extract.
- Camellia Japonica Leaf Extract plant extract
- The leaf extract of the Korean camellia, the same plant as the seed oil pressed on Jeju. It is used as a conditioning antioxidant extract.
- Centella Asiatica Extract plant extract
- Centella Asiatica is the plant behind the whole cica category, sold as gotu kola or Madagascar centella. Its extract is the anchor of Korean formulas built for easily reddened skin, and its work is done by four triterpenes: asiaticoside, madecassoside, asiatic acid and madecassic acid.
- Willow Bark Extract plant extract
- Willow Bark Extract carries salicin, the plant compound salicylic acid is related to. The two are not interchangeable: willow bark is a mild clarifying extract, not a BHA exfoliant at the levels used in cosmetics.
- Phellodendron Amurense Bark Extract plant extract
- Amur cork tree bark, another traditional berberine-bearing herbal ingredient. It is yellow and appears in blends aimed at the look of congested skin.
- Citrus Paradisi (Grapefruit) Seed Extract plant extract
- Grapefruit seed extract. It is used as a conditioning plant extract and, because it resists microbes, often as part of a preservative system.
- Magnolia Officinalis Bark Extract plant extract
- Magnolia bark extract, carrying magnolol and honokiol. It resists microbes as well as conditioning, so it often forms part of a preservative system.
- Camellia Sinensis Leaf Extract plant extract
- Camellia Sinensis is the tea plant. Green tea leaf extract carries catechins, among the most studied plant antioxidants, and is used for the look of redness and oily shine.
- Oryza Sativa (Rice) Extract plant extract
- Rice Extract is the anchor of the Korean rice-skincare category. It carries starches, amino acids and ferulic acid, and it is used for the look of dullness and for a soft, blurred finish.
- Benzyl Alcohol preservative
- Benzyl Alcohol is an aromatic alcohol that occurs naturally in jasmine and ylang ylang. It is a preservative and a solvent, and it is also one of the 26 declarable fragrance components.
- Lavandula Angustifolia (Lavender) Water plant extract
- Lavender distillate, used in place of part of the plain water in a formula. It is much more dilute than an extract or an oil.
- Borago Officinalis Extract plant extract
- Borage extract. The plant is best known for the gamma-linolenic acid in its seed oil, while the water extract carries mucilage that holds water at the surface.
- Artemisia Vulgaris Extract plant extract
- Common mugwort extract. It is the same genus as the Korean mugwort artemisia princeps and is used for the look of reddened, reactive skin.
- Chamomilla Recutita (Matricaria) Flower/Leaf Extract plant extract
- German chamomile, taken from flower and leaf together. It carries bisabolol and the blue azulenes and is used for the look of reactive, reddened skin.
- Salvia Sclarea (Clary) Extract plant extract
- Clary sage extract, carrying flavonoids and tannins. It is the water-based extract and a different ingredient from clary sage essential oil.
- Hyacinthus Orientalis (Hyacinth) Extract plant extract
- Hyacinth extract, used as a floral herbal extract. It is one of the less common botanicals to meet on a Korean label.
- Centaurea Cyanus Flower Extract plant extract
- Cornflower extract, a traditional eye-area ingredient in European pharmacy. It carries flavonoids and anthocyanins and is used in gentle formulas.
- Tocopherol antioxidant
- Tocopherol is vitamin E. It is an oil-soluble antioxidant that protects the oils in a formula from going rancid and works on skin as an emollient, and it is regularly paired with vitamin C because each keeps the other going for longer.
- Sophora Angustifolia Root Extract plant extract
- Gosam root extract, a bitter traditional Korean herbal root. It is used as a conditioning extract, usually in blends aimed at the look of congested skin.
- Melia Azadirachta Extract plant extract
- Neem extract with the plant part unstated. Neem carries limonoid compounds and is a long used botanical in Indian practice, and the extract is used as a conditioning extract.
- Citrus Paradisi (Grapefruit) Fruit Extract plant extract
- Grapefruit fruit extract, carrying fruit acids, sugars and flavonoids. It is used as a conditioning, antioxidant-rich extract.
- Market
- Korean market, the version sold in Korea
- EAN (barcode)
- 8809883888574
- Made in
- Republic of Korea
- Volume
- 55ml
- Category
- Serum & Ampoule
- Actives
- Centella Asiatica, Green Tea, Licorice Root, Mugwort, Rice Extract, Salicylic Acid, Tea Tree
- Ships from
- California or Korea
Orders ship from California or direct from Korea with tracked delivery to your door, and both routes carry the same Korean-market release. Shipping is free on orders of $100 or more. Returns are accepted for 30 days, by mail.
We split shipments free, so one out-of-stock item never holds up the rest of your order.
Where this unit came from
- 1Seoul
Bought as Korean-market stock - 2Barcode
Listed against the Korean barcode on its box - 3California or Korea
Ships to you from either, as the same Korean-market release
We stock the version of a formula that is sold in Korea, not the release a brand prepares for another market under the same name. The barcode in the specification above is the Korean-market one and it is printed on the box you receive.
Every unit keeps its original barcode and batch code intact, so the unit in your hands can be checked against the brand’s own records.
Every order ships from California or direct from Korea, and returns run for 30 days.
Every claim on this page traces to the unit in the box, the barcode, the batch code and the price you can read for yourself.
How it works
Medicube Red Serum Plus is a serum built for the treatment step right after toner. Its ingredient list leads with Salicylic Acid, Melaleuca Alternifolia (Tea Tree) Leaf Oil, and Centella Asiatica Extract, so the formula's stated purpose lines up with what actually sits near the top of that list rather than with a single marketing ingredient buried further down. Salicylic Acid does the most work here as a pore care, and the remaining actives round out the texture and finish rather than compete for attention. Placed as the treatment step right after toner, it is meant to be used AM/PM rather than swapped freely between steps. Because this is the Korean-market version of the Red Serum Plus line rather than a US-reformulated variant, the texture and finish match what Medicube sells through Korean retail.
How to use
- Use the Red Serum Plus after toner and before moisturizer, in the evening.
- Three or four drops covers the whole face. Press it in with flat palms instead of rubbing it around.
- Toner first so the surface is damp, then this, then about a minute before your moisturizer goes over the top. Salicylic acid is the entry that puts this step in the evening rather than the morning.
- Start at two or three evenings a week and build up from there, because salicylic acid is on this list. Do not use it in the same routine as another resurfacing acid or a retinoid.
Worth knowing
- Patch test on the inner arm before the first full-face application, especially on skin that reacts easily to new products.
- Stop use and rinse off if stinging, burning, or new redness shows up rather than pushing through discomfort.
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Medicube Red Serum Plus
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Medicube, Korean-market original
Medicube's Korean-market serum led by Salicylic Acid, the same formula sold in Korea.
Verify your unit when it arrives
Verify your unit when it arrives
Korean-market stock with the original barcode and batch code intact, exactly as it left Korea.
Medicube prints a QR code on the inner box. Scan it with your phone camera and it resolves to the brand’s own verification site.
Verify on medicubeverify.com →Source: Medicube packaging and verification site
On the unit itself
- The Korean-market barcode, unaltered from the retail package.
- The manufacturer’s batch code, exactly as the maker printed it.
정품Genuine article, Korean-market stock
What professionals say
What professionals say
What skin-care professionals say about the key actives in this formula, quoted from the medical sources linked beside each.
BHAs like salicylic acid get really deep into the pores, whereas the water-soluble ones don't go as deep.
Samantha Stein, PA-CDermatology physician assistant, Cleveland Clinic I think it's fair to say I've seen lots of patients use tea tree oil for a variety of skin issues. It's a natural remedy that is known to help.
Simon Hodes, MB ChBFamily physician, Cleveland Clinic
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