Advanced Pure Vitamin C 23 SerumCOSRX Advanced Pure Vitamin C 23 Serum, Renewal Edition, 20 ml (0.7 fl oz)

The same strength, without the old scent

This Renewal Edition keeps the 23% vitamin C level of the earlier formula but removes the distinctive smell it used to carry. The texture is light and leaves no sticky residue, so it layers easily under moisturiser.

Plan it around your other actives

COSRX advises against using this serum at the same time as high-strength peptide products, retinol or its own Niacinamide 15 Serum. A simple approach is to keep vitamin C for one part of the day and stronger actives for another.

Keeping vitamin C fresh

Pure vitamin C is prone to oxidation, so the brand suggests keeping the bottle in the fridge once opened. Squalane, panthenol, caffeine and sodium hyaluronate also feature in the ingredient list.

How to use

After cleansing and toning, shake the bottle gently once or twice and apply 2 to 3 drops to the face, once or twice a day. It can be used around the eye area, but avoid direct contact with the eyes. Follow with moisturiser, and with SPF 30 or higher during the day.

Before you choose

This is a concentrated cosmetic serum, so the manufacturer recommends a patch test: apply a little to a discreet area and wait 24 hours before using it on the face. For external use only. Stop using it and speak to a healthcare professional if irritation develops. Korean-market product: packaging may show Korean text.

Full ingredients

Dimethicone, Panthenol, 3-O-Ethyl Ascorbic Acid, Squalane, Caffeine, Sodium Hyaluronate, Glutathione, Adenosine, Niacinamide, Ascorbic Acid (23%), Water, Tocopherol, Arginine, Glycyrrhiza Glabra (Licorice) Root Extract.

Check your bottle for the formulation supplied.

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