Red Serum
Medicube Red Serum is a serum that names Zinc PCA on its own ingredient panel, sourced as the Korean-market formula.
No reviews yet30ml
$89.97 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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Key benefits
- Zinc PCA named on this product's own ingredient panel
- Niacinamide on the same panel, the formula's active
- Dipotassium Glycyrrhizate on the same panel, the formula's active
- 30 ml to a unit
- Korean-market formula, with its Korean barcode and batch code intact on the box
Key actives
8Niacinamide
Niacinamide is vitamin B3, and it is the most studied active in Korean formulation. It is used at roughly 2 to 5 percent for the look of uneven tone and visible pores, and it is water soluble, stable and comfortable beside almost every other active, which is why it turns up in so many lists.
20Dipotassium Glycyrrhizate
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.
22Zinc PCA
Zinc PCA pairs zinc with the humectant PCA. It is used in oily and blemish-prone formulas for the look of shine and visible pores, and it hydrates at the same time.
24Salicylic Acid
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.
Inside the formula
Inside the formula
- 8Niacinamide
- 20Dipotassium Glycyrrhizate
- 24Salicylic Acid
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
What does the Red Serum actually contain?
Its ingredient list is led by Niacinamide, 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?
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 the same formula sold in Korea, or a US version?
This Red Serum 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 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 suited for?
It suits most skin types looking for treatment step right after toner rather than a single acute problem. It comes in a 30ml 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: fragrance or parfum, parabens, sulfate surfactants, mineral oil or petrolatum and added color.
Full INCI (62): Red Serum 2.0 Water, Dipropylene Glycol, Glycerin, Xylitol, Alcohol Denat., Propanediol, 1,2-Hexanediol, Niacinamide, Trehalose, Diethoxyethyl Succinate, Betaine, Pentylene Glycol, Butylene Glycol, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, C12-14 Alketh-12, Dimethicone Crosspolymer, Polyisobutene, Ammonium Acryloyldimethyltaurate/VP Copolymer, Vinyl Dimethicone, Dipotassium Glycyrrhizate, Tromethamine, Zinc PCA, Carbomer, Salicylic Acid, Hydrogenated Lecithin, Isododecane, Allantoin, Dimethyl Sulfone, Panthenol, Polyquaternium-51, 4-Terpineol, Melaleuca Alternifolia (Tea Tree) Leaf Oil, Caprylyl/Capryl Glucoside, Sorbitan Oleate, Adenosine, Ethylhexylglycerin, Melia Azadirachta Leaf Extract, Melia Azadirachta Flower Extract, Caprylic/Capric Triglyceride, Xanthan Gum, Coccinia Indica Fruit Extract, Ocimum Sanctum Leaf Extract, Aloe Barbadensis Flower Extract, Solanum Melongena (Eggplant) Fruit Extract, Curcuma Longa (Turmeric) Root Extract, Corallina Officinalis Extract, Ceramide NP, Sodium Stearoyl Glutamate, Tocopherol, Lactococcus Ferment Lysate, Decyl Glucoside, Camellia Sinensis Leaf Extract, Centella Asiatica Leaf Extract, Cladosiphon Okamuranus Extract, Salix Alba (Willow) Bark Extract, Coffea Arabica (Coffee) Seed Extract, Sodium Chloride, Phenylpropanol, Citrus Aurantium Bergamia (Bergamot) Leaf Extract, Levulinic Acid, Sodium Levulinate, Pinus Densiflora Leaf ExtractRutin
59 of 62 explained
- 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.
- 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.
- 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.
- Alcohol Denat solvent
- Alcohol Denat. is ethanol with a bitter additive that makes it undrinkable, which is a tax rule rather than a formulation choice. It behaves like alcohol: a fast-evaporating solvent that gives a weightless finish and can feel drying at higher levels.
- 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.
- 1,2-Hexanediol humectant
- 1,2-Hexanediol is a glycol used for two reasons: it holds water like glycerin, and it makes a formula harder for microbes to live in, so less traditional preservative is needed. Korean formulas use it heavily for that second reason.
- Niacinamide active
- Niacinamide is vitamin B3, and it is the most studied active in Korean formulation. It is used at roughly 2 to 5 percent for the look of uneven tone and visible pores, and it is water soluble, stable and comfortable beside almost every other active, which is why it turns up in so many lists.
- Trehalose humectant
- Trehalose is a sugar that some desert plants use to survive drying out. In skincare it is a humectant that holds water in the outer layer and helps a formula feel comfortable rather than tight.
- 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.
- 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.
- Pentylene Glycol humectant
- Pentylene Glycol hydrates and, like the other longer-chain glycols, makes a formula less hospitable to microbes so the preservative system can be lighter. It also improves how evenly a product spreads.
- 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.
47 more explained
- Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer thickener
- This is a pre-neutralised polymer thickener that gels on contact with water and stabilises an emulsion without heat.
- C12-14 Alketh-12 emulsifier
- C12-14 Alketh-12 is a solubiliser used to keep oils and fragrance dissolved in a water-based formula.
- Dimethicone Crosspolymer silicone
- Dimethicone Crosspolymer is silicone linked into a soft, springy network. It soaks up oil, blurs the look of texture, and gives the velvety feel of a primer.
- Polyisobutene film former
- Polyisobutene is a synthetic polymer that forms a flexible, water-resistant film. It gives gloss and holds a formula in place, which is why it appears in lip products and long-wear textures.
- Ammonium Acryloyldimethyltaurate/VP Copolymer thickener
- This is a synthetic thickener that gels quickly and holds an emulsion stable across a wide pH range. It gives a light, non-tacky body.
- Vinyl Dimethicone silicone
- Vinyl Dimethicone is a silicone used as a building block of the crosspolymer gels that give a formula its soft, blurring feel.
- 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.
- Tromethamine pH adjuster
- Tromethamine neutralises acidic thickeners such as carbomer so they gel, and holds a formula near skin-friendly pH. It is used at a fraction of a percent.
- Zinc PCA active
- Zinc PCA pairs zinc with the humectant PCA. It is used in oily and blemish-prone formulas for the look of shine and visible pores, and it hydrates at the same time.
- 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.
- 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.
- Hydrogenated Lecithin emulsifier
- Hydrogenated Lecithin is lecithin with its unsaturated bonds filled in, which makes it far more stable. It emulsifies and is the standard shell for the liposomes that carry actives into the outer layer of skin.
- Isododecane solvent
- Isododecane is a light, volatile hydrocarbon. It carries pigments and film formers on smoothly and then evaporates, leaving the film behind and nothing oily.
- Allantoin active
- Allantoin is a comfrey-derived compound used to condition skin and soften the outer layer so it feels smoother. It is one of the standard additions to a formula built for easily irritated skin.
- Dimethyl Sulfone solvent
- Dimethyl Sulfone is MSM, an organic sulfur compound that dissolves in water. It is used as a conditioning ingredient and as a carrier for other actives.
- Panthenol humectant
- Panthenol is pro-vitamin B5: skin converts it to pantothenic acid. It is a humectant that holds water and leaves skin feeling soft and less tight, and it is one of the ingredients formulators reach for when a formula also contains something harsh.
- Polyquaternium-51 film former
- Polyquaternium-51 is a polymer, sometimes sold as Lipidure, built on the same phosphorylcholine structure as a cell membrane. It holds water in a film on the surface and gives a distinctive soft, dry finish.
- 4-Terpineol fragrance component
- A terpene alcohol, and the main constituent of tea tree oil. On a label it is an aromatic plant constituent rather than a functional ingredient.
- 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.
- Caprylyl/Capryl Glucoside surfactant
- Caprylyl/Capryl Glucoside is a sugar-derived cleansing surfactant. It foams modestly and is mild enough for low-pH cleansers built for reactive skin.
- Sorbitan Oleate emulsifier
- Sorbitan Oleate is an emulsifier for water-in-oil formulas. It keeps a rich cream or a cleansing oil from separating.
- Adenosine active
- Adenosine is a nucleoside that Korea's own cosmetic authority recognises as a wrinkle-care functional ingredient, which is why it appears on so many Korean lists at a low level. It is used for the look of fine lines and is stable and well tolerated.
- Ethylhexylglycerin preservative booster
- Ethylhexylglycerin softens skin and boosts a preservative system, which is why it is nearly always sitting beside phenoxyethanol or 1,2-hexanediol. It also cuts down the odour bacteria produce, so it turns up in deodorising products.
- Melia Azadirachta Leaf Extract plant extract
- Melia Azadirachta is neem. Its leaf and flower extracts are long-standing Ayurvedic ingredients, and Korean formulas use them in products aimed at the look of congested, blemish-prone skin.
- Caprylic/Capric Triglyceride emollient
- Caprylic/Capric Triglyceride is the light fraction of coconut oil, with the heavy parts removed. It is the workhorse emollient of modern formulas: it softens skin, dissolves oil-soluble actives and absorbs without the greasy weight of a whole plant oil.
- Xanthan Gum thickener
- Xanthan Gum is a polysaccharide made by fermenting sugar. It thickens a watery formula into a gel and holds the whole thing in suspension so nothing separates. Too much of it and a serum turns stringy, which is why it appears in fractions of a percent.
- Coccinia Indica Fruit Extract plant extract
- Coccinia Indica is ivy gourd. Its fruit extract is used as a conditioning, hydrating plant extract in Korean formulas.
- Ocimum Sanctum Leaf Extract plant extract
- Ocimum Sanctum is holy basil, or tulsi. Its leaf extract carries plant antioxidants and is used in formulas built for the look of stressed, reactive skin.
- Aloe Barbadensis Flower Extract plant extract
- Aloe Flower Extract comes from the flower rather than the leaf gel. It is used as a conditioning plant extract.
- Solanum Melongena (Eggplant) Fruit Extract plant extract
- Eggplant Fruit Extract carries nasunin, the antioxidant pigment in aubergine skin. It is used as an antioxidant plant extract.
- Curcuma Longa (Turmeric) Root Extract plant extract
- Turmeric Root Extract carries curcuminoids, well studied plant antioxidants. It is used for the look of dullness and uneven tone, and it tints a formula faintly yellow.
- Corallina Officinalis Extract plant extract
- Corallina Officinalis is coral seaweed, which holds calcium and magnesium in its structure. Its extract is used as a mineral-rich conditioning ingredient.
- Ceramide NP barrier lipid
- Ceramide NP is the most used cosmetic ceramide, the same class of lipid that makes up roughly half the mortar between cells in the outer layer of skin. Added to a cream it slots into that structure, which is why ceramide formulas feel less leaky rather than merely greasy.
- Sodium Stearoyl Glutamate emulsifier
- Sodium Stearoyl Glutamate is an amino-acid-derived emulsifier. It holds oil and water together and is mild enough for formulas built for reactive skin.
- 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.
- Lactococcus Ferment Lysate ferment
- Lactococcus Ferment Lysate is a lactic-culture ferment with the bacterial cells broken open, so their contents are in the formula too. It is used as a conditioning ferment in barrier-focused products.
- Decyl Glucoside surfactant
- Decyl Glucoside is a sugar and coconut-derived surfactant, one of the mildest cleansers available. It produces a soft, low foam and rinses without stripping.
- 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.
- Centella Asiatica Leaf 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.
- Cladosiphon Okamuranus Extract plant extract
- Cladosiphon Okamuranus is Okinawan mozuku seaweed, the main commercial source of fucoidan. Its extract is used as a hydrating polysaccharide ingredient.
- Salix Alba (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.
- Coffea Arabica (Coffee) Seed Extract plant extract
- Coffee Seed Extract carries caffeine and chlorogenic acid. It is used as an antioxidant extract and, in eye and body formulas, for the look of puffiness.
- Sodium Chloride thickener
- Sodium Chloride is salt. In a cleanser it thickens the liquid; in a mask or essence it balances the mineral content of the water phase. It has no active role.
- Phenylpropanol solvent
- Phenylpropanol is an aromatic alcohol with a faint hyacinth smell. It works as a solvent and strengthens a preservative system, so it appears in formulas built without parabens.
- Citrus Aurantium Bergamia (Bergamot) Leaf Extract plant extract
- Bergamot Leaf Extract is the water-based leaf extract rather than the peel oil, so it is far milder and much less aromatic.
- Levulinic Acid preservative
- Levulinic Acid is a plant-derived acid used with its sodium salt as a natural preservative system. It also adjusts pH.
- Sodium Levulinate preservative
- The sodium salt of levulinic acid, and the other half of a plant-derived preservative pair. It is used in formulas built without traditional preservatives.
- Market
- Korean market, the version sold in Korea
- Made in
- Republic of Korea
- Volume
- 30ml
- Category
- Serum & Ampoule
- Actives
- Adenosine, Allantoin, Aloe Vera, Centella Asiatica, Ceramide NP, Green Tea, Licorice Root, Niacinamide, Panthenol, Salicylic Acid, Tea Tree, Trehalose, Zinc PCA
- 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.
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
Zinc PCA is named on the ingredient panel on this serum. Zinc PCA pairs zinc with the humectant PCA. It is used in oily and blemish-prone formulas for the look of shine and visible pores, and it hydrates at the same time. On this panel it sits alongside Niacinamide, Dipotassium Glycyrrhizate and Salicylic Acid. Niacinamide is vitamin B3, and it is the most studied active in Korean formulation. It is used at roughly 2 to 5 percent for the look of uneven tone and visible pores, and it is water soluble, stable and comfortable beside almost every other active, which is why it turns up in so many lists.
How to use
- Use the Red Serum 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
How it felt, how your skin took it, what you layer it with. Straight answers help the next person choose.
Medicube, Korean-market original
Medicube's Korean-market serum led by Niacinamide, 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.
It contains liquiritin, an active compound that helps to disperse and remove existing melanin in the skin.
Jennifer Chwalek, MDDermatologist, Byrdie 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
1 more professional perspective
Niacinamide helps reduce the appearance of pores in a few ways. By strengthening the skin barrier and improving elasticity, pores appear less noticeable and more even.
Ashlyn YankeAesthetician, Cleveland Clinic
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