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Product photo: cosrx.com (official brand store). The pack size shown may differ from the Korean 20g.
The Vitamin C 23 Serum
A potent vitamin C serum with 23% ethyl ascorbic acid in a silicone base, for brightening and dark spots.
- Key ingredient
- 3-O-ethyl ascorbic acid, Glutathione, niacinamide and adenosine
- Texture
- Silky, slightly oily serum from a silicone base
- Routine step
- serum · AM
- Korean pack
- 20g
Overview
Key ingredients
- 3-O-ethyl ascorbic acid Stable vitamin C derivative for brightening
- Glutathione, niacinamide and adenosine Supporting brightening and anti-ageing ingredients
- Squalane Softens the finish
From the US, it's 44% cheaper in Seoul after tax and refund. From the UK, it's 23% cheaper in Seoul.
What it is
COSRX’s The Vitamin C 23 Serum (now labelled Advanced The Vitamin C 23) is a 20g serum with a high level of vitamin C derivative in a water-free base.
Who it suits
Normal, combination and oily skin targeting dullness and dark spots. Sensitive skin may prefer a lower strength like Klairs Freshly Juiced Vitamin Drop.
How to use it
A few drops in the morning before moisturiser and sunscreen.
How it compares
By Wishtrend Pure Vitamin C 21.5 uses pure ascorbic acid instead. Goodal Green Tangerine is gentler.
FAQ
Does it tingle?
High-strength vitamin C can tingle. Start every other day.
Is it stable?
Ethyl ascorbic acid is more stable than pure vitamin C, and the water-free base helps.
