Below is every ingredient in Cosrx The Vitamin C 23 Serum 20 Gm 17 explained, its standout actives, and the side effects reported in research for those actives — analysed for Indian skin.
Flags derived from the ingredient list using dermatology reference data (fungal-acne substrate, comedogenicity, EU allergens). General guidance, not a diagnosis.
Answers are derived from the printed ingredient list and dermatology reference data — general guidance, not a diagnosis or a therapeutic claim.
Ascorbic acid (vitamin C) is a water-soluble antioxidant used in skincare to neutralize free radicals, inhibit melanin synthesis, and support collagen production. It is valued for brightening, evening skin tone, and protecting against photodamage when used alongside sunscreen.
Ethyl Ascorbyl Ether (3-O-ethyl ascorbic acid) is a stable, water- and oil-soluble vitamin C derivative that converts to ascorbic acid in the skin. It is used for antioxidant protection, brightening, and inhibition of melanin synthesis.
Caffeine is a topical active used in skincare for its antioxidant properties and ability to constrict blood vessels, which may temporarily reduce puffiness and the appearance of under-eye darkness. It is also studied for reducing localized fluid retention and protecting against UV-induced oxidative stress.
Glutathione is a tripeptide antioxidant used in skincare for its melanin-modulating and antioxidant properties, often promoted to reduce hyperpigmentation and even skin tone. Topical efficacy data is limited and variable, with stronger systemic effects associated with oral or intravenous routes.
Adenosine is a nucleoside that signals through cell-surface receptors to promote dermal fibroblast activity and collagen/elastin production, helping reduce the appearance of fine lines and wrinkles. It also has anti-inflammatory and soothing properties at low concentrations commonly used in cosmetics (around 0.04-0.1%).
Acetyl glucosamine is an amino sugar that serves as a precursor to hyaluronic acid and can help support skin hydration and barrier function. It is also studied for its ability to reduce hyperpigmentation by inhibiting melanin production, often used alongside niacinamide.
Aggregated from the active ingredients in this product.
| Reported effect | How often | Notes |
|---|---|---|
| Skin dryness or barrier disruption with excessive contact | Uncommon | Frequent or prolonged exposure to water, especially hot or hard water, can disrupt the skin barrier and contribute to transepidermal water loss. |
| Irritation from impurities or hard water minerals | Rare | Reactions are attributed to contaminants, chlorine, or mineral content rather than water itself. |
| Mild stinging or tingling on application | Common | More likely at higher concentrations or low pH, and on sensitive or compromised skin. |
| Transient redness (erythema) | Uncommon | Usually temporary and resolves after acclimation or reducing frequency. |
| Dryness or skin irritation | Uncommon | Can occur with frequent use or in combination with other actives. |
| Allergic contact dermatitis | Rare | True hypersensitivity to ascorbic acid is infrequent; patch testing can confirm. |
| Yellow-orange skin staining from oxidized product | Rare | Caused by degraded (oxidized) formulations rather than the fresh active itself. |
| Mild skin irritation | Uncommon | Transient stinging or redness, more likely on compromised or sensitive skin. |
| Enhanced penetration of co-formulated irritants | Uncommon | As a penetration enhancer it may increase absorption and irritation potential of other actives. |
| Mild skin irritation or redness | Rare | Generally considered non-irritating; occasional mild reactions reported. |
| Clogged pores / comedogenic-related breakouts | Uncommon | Often anecdotal; dimethicone is largely regarded as non-comedogenic but may trap debris if skin is not cleansed well. |
| Eye irritation on accidental contact | Rare | Transient stinging or discomfort if product enters the eyes. |
| Mild transient skin irritation | Uncommon | Possible stinging or redness, particularly on compromised or sensitive skin. |
| Eye irritation | Uncommon | Can cause irritation upon direct ocular contact in concentrated form. |
Frequencies reflect typical cosmetic use reported in the literature, not a guarantee for your skin.
| Ingredient | What it does |
|---|---|
| Water Solvent/vehicle | Water is the most common base ingredient in cosmetic formulations, serving as a solvent that dissolves other ingredients and forms the bulk of emulsions and aqueous solutions. It is generally considered safe and non-irritating. |
| Ascorbic Acid Key active Antioxidant / brightening active | Ascorbic acid (vitamin C) is a water-soluble antioxidant used in skincare to neutralize free radicals, inhibit melanin synthesis, and support collagen production. It is valued for brightening, evening skin tone, and protecting against photodamage when used alongside sunscreen. |
| Propanediol Humectant/solvent | Propanediol is a plant-derived glycol used in skincare as a humectant, solvent, and penetration enhancer that improves moisturization and the spreadability of formulations. It also helps solubilize other ingredients and can boost the efficacy of certain actives. |
| Dimethicone Emollient/occlusive (silicone) | Dimethicone is a silicone-based polymer used in skincare to soften skin, smooth texture, and form a breathable protective barrier that reduces transepidermal water loss. It is widely used as a base/formulation ingredient rather than a therapeutic active. |
| Tromethamine pH adjuster / buffering agent | Tromethamine (trometamol, TRIS) is an organic amine base used in cosmetic and topical formulations to neutralize acidic components and stabilize pH. It functions primarily as a buffering and neutralizing agent rather than as a therapeutic active. |
| Panthenol Humectant / skin-conditioning agent | Panthenol (provitamin B5) is converted to pantothenic acid in the skin, where it acts as a humectant and helps support skin barrier function and hydration. It is also used for its soothing and mild anti-inflammatory properties in topical formulations. |
| Ethyl Ascorbyl Ether Key active Antioxidant / Vitamin C derivative | Ethyl Ascorbyl Ether (3-O-ethyl ascorbic acid) is a stable, water- and oil-soluble vitamin C derivative that converts to ascorbic acid in the skin. It is used for antioxidant protection, brightening, and inhibition of melanin synthesis. |
| Squalane Emollient / occlusive moisturizer | Squalane is a saturated, stable hydrocarbon derived from squalene (sourced from plants like olives or sugarcane, or shark liver) used as a lightweight emollient that softens skin and reinforces the skin barrier by reducing transepidermal water loss. It is well tolerated, non-comedogenic for most users, and serves as a base or carrier ingredient rather than a therapeutic active. |
| Caffeine Key active Antioxidant / vasoconstrictor | Caffeine is a topical active used in skincare for its antioxidant properties and ability to constrict blood vessels, which may temporarily reduce puffiness and the appearance of under-eye darkness. It is also studied for reducing localized fluid retention and protecting against UV-induced oxidative stress. |
| Sodium Chloride Thickener / viscosity adjuster | Sodium chloride (table salt) is commonly used in cosmetics as a thickening and viscosity-control agent, particularly in surfactant-based cleansers, and also acts as a mild abrasive in scrubs. It is generally well tolerated and considered a formulation ingredient rather than a treatment active. |
| Sodium Hyaluronate Humectant / hydrator | Sodium hyaluronate is the sodium salt of hyaluronic acid, a glycosaminoglycan that attracts and binds water to the skin to improve hydration and surface plumpness. Its lower molecular weight allows better penetration than native hyaluronic acid. |
| Sodium Sulfite Antioxidant/preservative | Sodium sulfite is an inorganic salt used in cosmetic formulations primarily as an antioxidant and preservative to prevent oxidation and discoloration of products. It is generally considered a formulation ingredient rather than a treatment active. |
| Disodium EDTA Chelating agent | Disodium EDTA is a chelating agent used in cosmetics to bind metal ions, improving product stability, preventing rancidity, and enhancing the efficacy of preservatives. It is a formulation/base ingredient rather than a treatment active. |
| Glutathione Key active Antioxidant / skin-brightening agent | Glutathione is a tripeptide antioxidant used in skincare for its melanin-modulating and antioxidant properties, often promoted to reduce hyperpigmentation and even skin tone. Topical efficacy data is limited and variable, with stronger systemic effects associated with oral or intravenous routes. |
| Adenosine Key active Anti-aging/soothing active | Adenosine is a nucleoside that signals through cell-surface receptors to promote dermal fibroblast activity and collagen/elastin production, helping reduce the appearance of fine lines and wrinkles. It also has anti-inflammatory and soothing properties at low concentrations commonly used in cosmetics (around 0.04-0.1%). |
| Acetyl Glucosamine Key active Skin-conditioning / exfoliant precursor | Acetyl glucosamine is an amino sugar that serves as a precursor to hyaluronic acid and can help support skin hydration and barrier function. It is also studied for its ability to reduce hyperpigmentation by inhibiting melanin production, often used alongside niacinamide. |
| Gardenia Florida Fruit Extract Key active Antioxidant/skin-conditioning extract | Gardenia Florida Fruit Extract is a botanical derived from the fruit of the gardenia plant, rich in iridoid glycosides (such as geniposide and genipin) and crocin pigments that provide antioxidant and soothing properties. It is used in skincare for its potential to protect against oxidative stress and condition the skin. |
| Allantoin Key active Soothing/skin-conditioning agent | Allantoin is a naturally derived or synthetically produced compound used in skincare for its soothing, moisturizing, and keratolytic (skin-softening) properties. It promotes cell proliferation and helps calm irritation, commonly appearing in creams, lotions, and after-sun products. |
| Dextrin Thickener / absorbent / emulsion stabilizer | Dextrin is a polysaccharide derived from the partial hydrolysis of starch, commonly used in cosmetics as a thickening agent, absorbent, and binder to improve texture and stability of formulations. It is considered a formulation ingredient rather than an active treatment. |
| Tocotrienols Key active Antioxidant | Tocotrienols are a subgroup of vitamin E compounds used in skincare for their antioxidant activity, helping protect skin lipids from oxidative damage caused by UV exposure and environmental stressors. They are often combined with tocopherols and other antioxidants to enhance stability and skin protection. |
| Tocopherol Key active Antioxidant | Tocopherol (vitamin E) is a lipid-soluble antioxidant used in skincare to protect skin and formulations from oxidative damage caused by free radicals and UV exposure. It also functions as a skin-conditioning and emollient agent and can stabilize oils against rancidity. |
| Elaeis Guineensis Oil Emollient / skin-conditioning oil | Elaeis Guineensis (palm) oil is a plant-derived lipid used as an emollient and occlusive in skincare to soften skin and reinforce the skin barrier. It is rich in palmitic and oleic fatty acids and naturally contains tocopherols and carotenoids. |
| Butylene Glycol Humectant / solvent | Butylene glycol is a small diol commonly used in skincare as a humectant, solvent, and viscosity-reducing agent that helps dissolve other ingredients and improve skin feel. It is widely regarded as safe and non-sensitizing for the majority of users at cosmetic concentrations. |
| Arginine Amino acid / pH adjuster & conditioning agent | Arginine is a basic amino acid used in skincare primarily as a pH buffer/neutralizer and humectant-like conditioning agent that supports skin hydration and barrier function. It is generally well tolerated and often paired with acidic ingredients to balance formulation pH. |
| Niacinamide Key active Cell-communicating / barrier-repair active | Niacinamide (vitamin B3) is a water-soluble active that supports the skin barrier, regulates sebum, brightens hyperpigmentation, and reduces inflammation. It is widely tolerated across skin types and used in concentrations commonly ranging from 2% to 10%. |
| Pentylene Glycol Humectant / solvent / preservative-booster | Pentylene glycol is a glycol used in cosmetics as a humectant and solvent that also enhances the antimicrobial efficacy of formulations, helping reduce reliance on traditional preservatives. It improves skin hydration and aids the delivery and stability of other ingredients. |
| Alcohol Denat Solvent/penetration enhancer | Alcohol Denat (denatured ethanol) is a volatile solvent used in skincare to dissolve other ingredients, improve product spreadability and absorption, and create a quick-drying, lightweight feel. It is a formulation aid rather than a therapeutic active. |
| Helianthus Annuus Seed Oil Emollient / skin-conditioning oil | Helianthus Annuus (Sunflower) Seed Oil is a plant-derived emollient rich in linoleic acid and vitamin E, used to soften skin and support the skin barrier. It is widely used as a base oil in moisturizers and cosmetic formulations. |
| Glycyrrhiza Glabra Root Extract Key active Soothing / brightening agent | Glycyrrhiza Glabra (licorice) Root Extract is a botanical ingredient containing glycyrrhizin and glabridin, valued for its anti-inflammatory and skin-brightening properties. It is commonly used to calm irritation, reduce redness, and help fade hyperpigmentation by inhibiting tyrosinase activity. |
| Methyl Trimethicone Volatile silicone emollient/spreading agent | Methyl Trimethicone is a lightweight, volatile silicone used in skincare and cosmetics to provide smooth, non-greasy spreadability and a silky skin feel. It evaporates after application, leaving a dry, soft finish without significant residue. |
| Carthamus Tinctorius Seed Oil Emollient / skin-conditioning oil | Carthamus Tinctorius (Safflower) Seed Oil is a plant-derived oil rich in linoleic acid used as an emollient and moisturizing agent in skincare. It helps soften skin, support the lipid barrier, and improve the texture and spreadability of formulations. |
| Camellia Japonica Seed Oil Emollient / skin-conditioning oil | Camellia Japonica Seed Oil is a plant-derived oil rich in oleic acid and antioxidants used to soften, moisturize, and reinforce the skin barrier. It functions primarily as an emollient and occlusive agent in skincare formulations. |
| Daucus Carota Sativa Root Extract Key active Antioxidant / skin conditioning | Daucus Carota Sativa (carrot) Root Extract is a botanical extract rich in carotenoids, vitamins, and antioxidants used in skincare for conditioning, brightening, and protective effects against oxidative stress. It is commonly included for its skin-soothing and replenishing properties. |
| Beta-Carotene Key active Antioxidant / provitamin A colorant | Beta-carotene is a carotenoid pigment and provitamin A antioxidant used in skincare to help neutralize free radicals and provide mild orange-yellow coloration. It can be converted to retinol in the body and is also valued for supporting skin defense against oxidative stress. |
Key active = does the main work. Ingredient explanations are drawn from public databases & literature.
Peer-reviewed papers on the active ingredients in this product, via PubMed.