Sulwhasoo
The Ultimate S SerumThe Inkey List
10% Azelaic Acid Serum for Redness ReliefA serum built around Hyaluronic acid, for hydration and barrier repair.
A serum built around Azelaic acid, for pollution defence and hydration.
Brand price
USD 360.00 · checked 26 Sept 2026 · brand's site
Brand price
USD 20.00 · checked 26 Sept 2026 · brand's site
At a Glance
They come out differently on Fragrance-free, EU-allergen-free, Alcohol-free, Silicone-free, Pore-clogger-free, Vegan and Cruelty-free; those rows are shaded. Tap any answer to see why.
Key Ingredients
Hyaluronic acid1
Hyaluronic acid and its salts; a humectant that binds water to the skin.
Benefits
Hydrating18
Boosts hydration and relieves dry, tight skin.
Acetyl Heptapeptide-4, Acetyl Hexapeptide-8, Acetyl Octapeptide-3, Beta-Glucan, Bis-Peg-18 Methyl Ether Dimethyl Silane, Butylene Glycol, Dimethicone, Dimethiconol, Glycereth-26, Glycerin, Honey, Hydrolyzed Proanthocyanidin, Panax Ginseng Root Protoplasts, Propanediol, Sodium Hyaluronate, Sodium Polyaspartate, Tocopherol, Trehalose
Barrier Repair15
Strengthens and restores the skin's natural barrier.
Bis-Peg-18 Methyl Ether Dimethyl Silane, Caprylyl Glycol, Dimethicone, Dimethiconol, Glycerin, Hydrogenated Poly(C6-14 Olefin), Hydrogenated Polydecene, Hydrolyzed Proanthocyanidin, Panax Ginseng Berry Extract, Panax Ginseng Root Extract, Pentaerythrityl Tetraethylhexanoate, Phytosphingosine, PPG-5-LAURETH-5, Sodium Polyacrylate, Tocopherol
Concerns
May Worsen Seborrheic Dermatitis11
May feed the yeast involved in seborrheic dermatitis.
Acetyl Heptapeptide-4, Acetyl Hexapeptide-8, Acetyl Octapeptide-3, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Hydrogenated Lecithin, Hydrogenated Phosphatidylcholine, Phytosphingosine, Polysorbate 60, PPG-5-LAURETH-5, Sodium Methyl Stearoyl Taurate, Sorbitan Isostearate
May Worsen Keratosis Pilaris2
May clog follicles or strip skin prone to keratosis pilaris.
May Worsen Irritation5
May cause stinging, redness or sensitivity.
Alcohol Denat., Benzyl Salicylate, Fragrance, Limonene, Tocopherol
May Worsen Seborrheic Dermatitis2
May feed the yeast involved in seborrheic dermatitis.
May Worsen Keratosis Pilaris1
May clog follicles or strip skin prone to keratosis pilaris.
Ingredients Side-by-side
Skin Conditioning
Fragrance
0 / —
- Denatured alcohol
- May Worsen Dryness
- May Worsen Eczema
- May Worsen Irritation
- May Worsen Rosacea
Pentaerythrityl Tetraethylhexanoate
Emollient
Hydrogenated Poly(C6-14 Olefin)
Emollient
Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer (in both products)
Emulsion Stabilising
Fragrance
Ethylhexylglycerin (in both products)
Skin Conditioning
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
Glycerin
Denaturant, Fragrance, Hair Conditioning, Humectant, Oral Care, Perfuming, Humectant, Skin Protecting, Solvent, Viscosity Controlling
Glycerin may be plant, synthetic or animal depending on the supplier.
Learn more about Glycerin →Propanediol
Solvent, Viscosity Controlling
Propanediol is the organic compound that conforms to the formula
Learn more about Propanediol →Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
Emulsion Stabilising, Viscosity Controlling
Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer is a copolymer of sodium hydroxyethyl acrylate and acryloyldimethyl taurate monomers
Learn more about Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer →Ethylhexylglycerin
Deodorant, Skin Conditioning
Ethylhexylglycerin is the organic compound that conforms to the formula
Learn more about Ethylhexylglycerin →Xanthan Gum
Binding, Emulsion Stabilising, Gel Forming, Skin Conditioning, Cleansing, Emulsifying, Viscosity Controlling
Xanthan gum
Learn more about Xanthan Gum →Sorbitan Isostearate
Emulsifying
Sorbitan Isostearate isn't fungal acne safe.
Learn more about Sorbitan Isostearate →Polysorbate 60
Cleansing, Emulsifying
Polysorbate 60 isn't fungal acne safe.
Learn more about Polysorbate 60 →Sodium Hydroxide
Buffering, Denaturant
Sodium hydroxide
Learn more about Sodium Hydroxide →
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