
Medik8
C-Tetra Vitamin C Serum
30ml · 4.6★ (4,300)
Brightens · Gentle vitamin C
Best price
£35.49
£1.18/ml

30ml · 4.4 (8700 reviews)
A gentle azelaic acid treatment for redness, blemishes and post-blemish marks.
UK retailers we currently hold. Some links are affiliate links.
Free UK delivery over £40 · £0.576/ml
£17.29
ShopFree UK delivery over £25 · £0.652/ml
£19.57
ShopPrime delivery available · £0.684/ml
£20.52
ShopPrices are placeholder data and update automatically once retailer feeds are connected. Last checked 8/26/2026. Shop links are affiliate links.
What's doing the work
Azelaic Acid
A gentle multi-tasker for redness, blemishes and post-blemish marks.
Redness · Breakouts · Pigmentation · Uneven tone
Niacinamide
A form of vitamin B3 that supports the skin barrier and helps regulate oil.
Excess oil · Uneven tone · Texture · Redness
Squalane
A lightweight emollient that softens without heaviness.
Dryness · Compromised barrier
Full INCI list
Aqua, Azelaic Acid, Niacinamide, Glycerin, Squalane
Ingredient lists are indicative and should be confirmed on pack. Live formulation data requires a retailer or brand feed integration.
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The INKEY List
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Visible smoothing · Supports firmness
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