AESTURA
A-CICA 365 SOOTHING RELIEF SERUM pH4.5 40ml
A soothing serum, sold in a 40ml bottle, for skin that reddens easily and wants a calm middle step.
No reviews yet40 ml
$131.25 per 100 ml
- Korean-market formula
- Ships from California or direct from Korea
- Korean barcode and batch code intact
- Suited to
- Sensitive skinDry skinCombination skinNormal skin
- Helps with
- A calmer looking complexionComfort through the dayA light middle step
In stock. Arrives in 3 to 7 business days
We accept
You’re $100.00 away from free US shipping.
- 30-day returns
- Free US shipping on orders of $100 or more
- Tracked delivery to your door
How it works
It is a thin fluid rather than a gel, so a few drops cover the face and settle without a film. Pressed on damp skin it sinks in quickly and leaves the surface ready for a cream. It is doing a narrower job than an all-purpose lotion, and that is the reason it goes on before one. It goes on after your watery step and before the cream that seals everything down. The honest measure is the way the skin looks in the mirror once everything has settled.
Key benefits
- Niacinamide sits at position #6 of 33 on A-CICA 365 Soothing Relief Serum pH4.5's own manufacturer ingredient list.
- Squalane is also named on that same list, further down the formula.
- A-CICA 365 Soothing Relief Serum pH4.5 is a serum from AESTURA, taking the serum's usual place in a layered Korean routine.
- AESTURA ships A-CICA 365 Soothing Relief Serum pH4.5 here as the Korean-market formula, the same version sold on shelves in Korea, not a US-shelf reformulation.
- Sold with intact Korean-market barcode and batch coding rather than a US-retail relabel.
Inside the formula
Inside the formula
What is this product, and who is it for?
It is a soothing serum in a 40ml bottle, made for skin that reddens easily and wants a calm middle step. That is the difference from a cream, which is built mostly to hold what is already there rather than to concentrate one job into a thin layer. What you can judge yourself is how the skin looks and feels a few minutes later, and how it behaves under the rest of the routine.
Should I use this in the morning or at night?
Either, and most people do both. In the morning it goes after the toner and before moisturizer and sunscreen; at night it sits in the same slot with nothing after the cream. If you are only using it once a day, the evening is the simpler choice because nothing else has to fit over it.
Is a pea sized amount enough?
For a whole face, yes. Three or four drops, or a dab about that size, is the working amount, pressed in from the centre outward. Anything more mostly sits on the surface and ends up on a collar. Two thin applications a day do more than one heavy one.
Do I still need a moisturizer over it?
Yes. A serum is the concentrated thin step and a moisturizer is the layer that keeps it from drying off the surface over the next hour. Leaving a serum as the last step is the most common reason a routine stops feeling like it is doing anything. Apply it, wait a moment, then the cream.
Not on the ingredient list below: fragrance or parfum, denatured or SD alcohol, essential oils, parabens, sulfate surfactants, mineral oil or petrolatum and added color.
Full INCI (32): Water/Aqua/Eau, Glycerin, Butylene Glycol, Dipropylene Glycol, Betaine, Niacinamide, Gluconolactone, 1,2-Hexanediol, Diethoxyethyl Succinate, Tromethamine, Sucrose Stearate, Squalane, Hydrogenated Lecithin, Polyglyceryl-10 Stearate, Polyglyceryl-10 Laurate, Carbomer, Caprylyl Methicone, Polyacrylate Crosspolymer-6, Ethylhexylglycerin, Cholesterol, Xanthan Gum, Asiaticoside, Madecassic Acid, Asiatic Acid, Sodium Hyaluronate, Cellulose Gum, 3-O-Ethyl Ascorbic Acid, Zinc Pca, Sodium Gluconate, Glyceryl Caprylate, Madecassoside, Sodium Metaphosphate
Ingredient list read from inkeedecoder.com on 10 September 2026.
32 of 32 explained
- Water/Aqua/Eau 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- Gluconolactone exfoliant
- Gluconolactone is a PHA, the gentlest exfoliant class. Its molecule is too large to penetrate quickly, so it smooths the surface without the sting of an AHA, and it is a humectant at the same time.
- 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.
- 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.
- 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.
- Sucrose Stearate emulsifier
- Sucrose Stearate is a sugar-based emulsifier chosen for a light finish in formulas built for reactive skin.
- Squalane emollient
- Squalane is the stable, saturated version of squalene, a lipid human skin already makes. It is a light emollient that absorbs quickly, does not oxidise, and is one of the few oils widely considered safe for blemish-prone skin. Most cosmetic squalane is now from sugarcane or olive rather than shark.
20 more explained
- 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.
- Polyglyceryl-10 Stearate emulsifier
- Polyglyceryl-10 Stearate is a mild sugar-derived emulsifier that holds oil into water and thickens slightly.
- Polyglyceryl-10 Laurate emulsifier
- Polyglyceryl-10 Laurate is a sugar-derived emulsifier and solubiliser, mild enough to be a standard choice in Korean essences. It dissolves small amounts of oil into water without any tightening feel.
- 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.
- Caprylyl Methicone silicone
- Caprylyl Methicone is a silicone with a fatty tail, so it mixes with plant oils as well as with silicones. It gives a dry slip and helps disperse powders.
- Polyacrylate Crosspolymer-6 thickener
- Polyacrylate Crosspolymer-6 is a thickener chosen for a notably fresh, bouncy gel feel that breaks down to water on the skin.
- 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.
- Cholesterol barrier lipid
- Cholesterol is the third of the three lipids the outer layer of skin is built from, with ceramides and fatty acids. Formulas that carry all three are following the ratio skin itself holds.
- 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.
- Asiaticoside active
- Asiaticoside is one of the four active triterpenes isolated from centella and the most studied of them. Korean formulas name it separately when they want to show which fraction of the plant they standardised.
- Madecassic Acid active
- Madecassic Acid is the fourth centella triterpene. A list that names all four is telling you the extract was standardised rather than simply pressed, which is the difference between a cica claim and a cica formula.
- Asiatic Acid active
- Asiatic Acid is the third of centella's four triterpenes and the aglycone form, meaning it has no attached sugar. It is oil soluble, so it turns up in cica creams and balms more than in watery layers.
- Sodium Hyaluronate humectant
- Sodium Hyaluronate is the salt of hyaluronic acid, and it is what most products labelled hyaluronic actually contain. The salt dissolves more readily and the molecule is smaller, so it sits in the outer layer of skin rather than only on top of it.
- Cellulose Gum thickener
- Cellulose Gum is plant cellulose modified to dissolve in water. It thickens, holds particles in suspension and gives a smooth, slippery body.
- 3-O-Ethyl Ascorbic Acid antioxidant
- 3-O-Ethyl Ascorbic Acid is a stable vitamin C derivative that skin converts to ascorbic acid. It survives in a formula far better than pure vitamin C and works at a gentler pH, so it suits skin that finds the pure acid uncomfortable.
- 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.
- Sodium Gluconate chelator
- The sodium salt of gluconic acid, used to tie up trace metals so a formula stays stable. It is one of the gentler chelators.
- Glyceryl Caprylate emulsifier
- Glyceryl Caprylate is a mild emulsifier that also makes a formula less hospitable to microbes, so it is often part of a preservative-free system.
- Madecassoside active
- Madecassoside is the centella triterpene most associated with the look of redness, and the one brands lead with in cica products. It is water soluble and stable, so it appears in essences as readily as in creams.
- Sodium Metaphosphate chelator
- A phosphate salt that ties up metal ions in water. It also stops the calcium and magnesium in hard water from flattening a cleanser foam.
- Market
- Korean market, the version sold in Korea
- EAN (barcode)
- 8809925189836
- Made in
- Republic of Korea
- Volume
- 40 ml
- Category
- Serum & Ampoule
- Actives
- Centella Asiatica, Madecassoside, Niacinamide, Sodium Hyaluronate, Squalane, Vitamin C, 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. 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 to use
- Apply it after your toner, while the face is still slightly damp, so a thin layer spreads without dragging.
- Three or four drops cover the whole face; press it in with the flats of the fingers rather than rubbing.
- Follow with a moisturizer within a minute so the thin layer has something holding it down.
- Do not stack it under a second serum doing the same job, since more layers is not the same as more result.
Worth knowing
- Patch test on a small area of the jaw first if your skin reacts easily to something new.
- Stop for a few days if the skin starts to sting, then bring it back on alternate evenings.
Complete the routine
- This itemAESTURA A-CICA 365 SOOTHING RELIEF SERUM pH4.5 40ml$52.50
- The treatment step of this routineAESTURA ATOBARRIER 365 HYDRO CERA-HA AMPOULE 30ml$42.50
- Seal the routine in as the last stepAESTURA Atobarrier 365 Hydro Soothing Cream 80ml$47.50
Total for 3 items$142.50
Reviews
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AESTURA A-CICA 365 SOOTHING RELIEF SERUM pH4.5 40ml
How it felt, how your skin took it, what you layer it with. Straight answers help the next person choose.
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AESTURA, Korean-market original
A soothing serum in a 40ml bottle that concentrates the calming part of a routine into one thin layer.
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.
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 skin care, quoted from the medical sources linked beside each.
Your skin barrier is basically your outer layer of the skin.
Melissa Piliang, MDDermatologist, Cleveland Clinic Pretty much every step of a Korean skin care routine is going to have some component of hydration.
Alok Vij, MDDermatologist, Cleveland Clinic
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