# COSRX The Vitamin C 23 Serum 20ml

A 20ml ascorbic acid serum for dull, uneven looking skin, stocked in the Original Korean Formula.

- Brand: COSRX
- Product: The Vitamin C 23 Serum 20ml
- Price: $37.50
- Availability: In stock
- Size: 20 ml
- Market: Korean market, the version sold in Korea
- Made in: Republic of Korea
- EAN (barcode): 8809598454651
- Category: Serums & Ampoules

## Key benefits

- Ascorbic Acid sits near the top on this product's own ingredient list, a vitamin C derivative included for its brightening, antioxidant role.
- A multifunctional glycol that carries moisture and helps preserve the formula, and Butylene Glycol is right there in this product's ingredient list, near the top.
- On this formula's own list, Panthenol shows up near the top. It is a barrier-supporting provitamin that eases surface roughness.

## How it works

This is the strong end of the tone shelf, and the tingle most people feel on application is the honest signal of that rather than a fault. It is a morning serum, both because the antioxidant side of it earns its place before a day out and because it sits happily under sunscreen. The small bottle is deliberate: an ascorbic acid formula is best used within a few months of opening rather than kept for a year. That is the difference from a milder derivative serum, which is comfortable from day one and keeps longer but works more gradually. What you can judge is whether the face reads clearer and more even in the same light after a month.

## How to use

1. After cleansing and toning, two or three drops cover the whole face, which is COSRX's own direction.
2. Apply after the toner on slightly damp skin, pressing a small amount over the face.
3. Wait a minute for the tingle to settle, then apply your moisturizer and finish with sunscreen.
4. Do not use it in the same sitting as an exfoliating product or a retinoid, and keep the bottle closed and out of the light.

## Ingredients

Aqua/Water, Ascorbic Acid(23%), Butylene Glycol, Dimethicone, Panthenol, 3-O-Ethyl Ascorbic Acid, Squalane, Sodium Hydroxide, Caffeine, Sodium Hyaluronate, Sodium Metaphosphate, Adenosine, Acetyl Glucosamine, Gardenia Florida Fruit Extract, Allantoin, Dextrin, Tocotrienols, Tocopherol, Elaeis Guineensis (Palm) Oil, Arginine, Niacinamide, Pentylene Glycol, Glutathione, Helianthus Annuus (Sunflower) Seed Oil, Methyl Trimethicone, Carthamus Tinctorius (Safflower) Seed Oil, Camellia Japonica Seed Oil, Daucus Carota Sativa (Carrot) Root Extract, Glycyrrhiza Glabra (Licorice) Root Extract, Beta-Carotene

## FAQ

### Will it sting?

Most people feel a tingle for up to a minute, which is normal for the strong end of this category. Stinging that does not settle is a signal to stop and choose a milder derivative serum instead.

### Where does it go in my routine?

In the morning, after the toner and before the moisturizer, with sunscreen as the last layer. The antioxidant side earns its place before a day out, and it sits under sunscreen without trouble. Wait a minute after applying before the next layer goes on.

### How long does it keep?

Use it within a few months of opening and keep the bottle closed and out of the light, since this kind of formula does not keep as long as a milder derivative. That is why the bottle is small. If it darkens noticeably, replace it rather than pushing on with it.

### Can I use it with a retinoid?

Not in the same sitting. Keep this to mornings and the retinoid to nights, which suits both, since a retinoid is broken down by light anyway. Stacking them together is how people end up flushed and peeling and then abandon both without learning which one suited them.

### Is this the Korean-market formula?

Yes. This is the Original Korean Formula 20ml bottle, the same one sold on Korean shelves.

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Page: https://korean-pharmacy.com/products/cosrx-the-vitamin-c-23-serum-20ml