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C-Tetra Advanced
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Medik8 C-Tetra Advanced 30ml

%0 4.8 | 1324 reviews
Box

£69.00 (£0.53 per g)

Free UK delivery

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If you like we can let you know when we have some more.

Product Description

Unlock next-generation brightening and antioxidant defence with C-Tetra® Advanced, powered by 20% stabilised vitamin C and skin barrier science. Clinically proven to brighten skin and visibly reduce wrinkles in just 7 days* with 0% barrier disruption,* this high-strength serum delivers transformative results without compromising skin health.

Featuring restorative phyto exosomes for deep, controlled delivery and omni-antioxidant acetyl zingerone to neutralise ageing free radicals, C-Tetra® Advanced provides targeted, age-defying protection and a visibly smoother, more radiant complexion.


*Proven via independent clinical study conducted over 4 weeks on 32 participants.

KEY BENEFITS
Dramatic Skin Brightening
Clinically proven to visibly brighten and even skin tone in just 7 days, revealing a radiant, luminous complexion.*

Enhanced Skin Barrier Support
Phyto exosomes deliver key signalling molecules, including peptides and nutrients, to support the skin barrier with 0% barrier disruption.*

Defence Against Premature Ageing
Shields skin from free radicals, pollution, and daily environmental stressors to help prevent premature skin ageing.

Smoother, More Even Texture
Clinically proven to improve skin smoothness and texture in 7 days, leaving a soft, polished finish.*

Lightweight, Fast-Absorbing Feel
The gel-serum texture hydrates, smooths, and primes skin, leaving it instantly refreshed and ready for the day.

20% Stabilised Vitamin C (Tetrahexyldecyl Ascorbate)
A highly potent yet gentle form of vitamin C for dramatic skin brightening and powerful antioxidant protection against premature skin ageing.

Phyto Exosomes
Encapsulated by nature, our phyto exosomes intelligently deliver proteins, lipids, and messenger molecules to skin cells. Together, alongside our supercharged vitamin C, they help prevent & reduce premature skin ageing by supporting healthier-looking, more resilient skin.

Acetyl Zingerone (pronounced ‘a-sea-tul')
A super-antioxidant that works synergistically with vitamin C, enhancing its efficacy while neutralising ageing free radicals and shielding skin from environmental stressors.

Multi-Weight Hyaluronic Acid
Draws moisture into the skin to instantly plump and deeply hydrate for a soft, supple complexion.

KEY INGREDIENTS
20% Stabilised Vitamin C (Tetrahexyldecyl Ascorbate)
A highly potent yet gentle form of vitamin C for dramatic skin brightening and powerful antioxidant protection against premature skin ageing.

Phyto Exosomes
Encapsulated by nature, our phyto exosomes intelligently deliver proteins, lipids, and messenger molecules to skin cells. Together, alongside our supercharged vitamin C, they help prevent & reduce premature skin ageing by supporting healthier-looking, more resilient skin.

Acetyl Zingerone (pronounced ‘a-sea-tul')
A super-antioxidant that works synergistically with vitamin C, enhancing its efficacy while neutralising ageing free radicals and shielding skin from environmental stressors.

Multi-Weight Hyaluronic Acid
Draws moisture into the skin to instantly plump and deeply hydrate for a soft, supple complexion.

N-Acetyl Glucosamine (NAG)
A barrier-supporting, gentle, skin-refiner that smooths the look of pores, while helping to increase the skin's own natural hyaluronic acid levels over time.

Directions

After cleansing in the morning, apply evenly across the face, neck & décolletage using upward strokes.

Test results

7 days to visibly brighter skin<1>
7 days to visibly reduced wrinkles<1>
0% barrier disruption<1>
7 days to visibly smoother skin texture<1>
Reduces 90% of pollution damage to the skin's surface<2>

<1> Proven via independent clinical study conducted over 4 weeks on 32 participants.
<2> Proven via in vitro protein carbonylation data against particulate matter pollution on the stratum corneum and epidermis.

Ingredients

Aqua (Water), Tetrahexyldecyl Ascorbate, Isododecane, Propanediol, Acetyl Glucosamine, Squalane, Tocopherol, Acetyl Zingerone, Camellia Sinensis (Green Tea) Leaf Vesicles, Hydroxyacetophenone, Sodium Hyaluronate, Cellulose, Avena Sativa (Oat) Kernel Extract, Glycerin, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Citrus Grandis (Grapefruit) Peel Oil, Sucrose Stearate, Tetrasodium Glutamate Diacetate, Ethylhexylglycerin, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Xanthan Gum, Sodium Benzoate, Cellulose Gum, 1,2-Hexanediol, Polysorbate 60, Sorbitan Isostearate, Citric Acid, Phenoxyethanol, Citral, Linalool, Limonene.

This list of ingredients may be subject to change, please consult the packaging of the product purchased.

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Rated 5 out of 5 by from Ticks all the boxes [This review was collected as part of a promotion.] Lovely. . . nice consistency, goes on nicely, soaks in nicely, smells nice and definitely helps brighten my dull skin. I must prefer the consistence to this than the some of the more oily vitamin c serums.
Date published: 2026-05-29
Rated 5 out of 5 by from Noticeably radiant results [This review was collected as part of a promotion.] Seriously good product. The texture is lovely it applies smoothly and effortlessly. I’ve already seen noticeable, visible improvements since adding Tetra C to my routine. My skin looks smoother and more radiant, and it’s become a permanent step in my skin care routine. I’m relatively new to Medik8 and discovered the brand through a friend’s recommendation. Adding Tetra C has genuinely improved the overall appearance of my skin. Highly recommend.
Date published: 2026-05-29
Rated 5 out of 5 by from great will re buy [This review was collected as part of a promotion.] love!!! Makes my skin feel soft soft and silky! protects my skin j wear it with the factor 50 medik8 sunscreen
Date published: 2026-05-28
Rated 5 out of 5 by from Fantastic product [This review was collected as part of a promotion.] Noticeable difference to my complexion within the first week of using vitamin c. Soaks into skin instantly. Will be purchasing as part of my skin routine.
Date published: 2026-05-27
Rated 5 out of 5 by from Worth trying I have previously experienced problems when using Vitamin C products but C-Tetra Advanced has caused me no irritation and my skin appears brighter.
Date published: 2026-05-26
Rated 5 out of 5 by from Velvet [This review was collected as part of a promotion.] It very much like velvet to apply. All I can said is, my friend said “are you applying something new to your face as your complexion looks really good”
Date published: 2026-05-26
Rated 5 out of 5 by from Great serum [This review was collected as part of a promotion.] Enjoying this serum. Skin feeling and looking brighter.
Date published: 2026-05-25
Rated 5 out of 5 by from Sublime under SPF [This review was collected as part of a promotion.] Having tried other vitamin C creams I was encouraged by a friend to try this. Started by using it in the U. K. but this really came into its own on a recent trip to Marrakesh. I used this u see my SPF 50. It has a lovely texture and sinks in beautifully. There was no pilling when I added my SPF. After 10 day trip in high heat ( sat in the shade with a cap when by the pool; wore a cap when sightseeing) I didn't tan and my skin looked luminous. I am 55, combination skin and have previous sun damage so actively trying to minimise any additional damage. Can't wait to try Exo-PDRN Prismatic+ with this when it arrives.
Date published: 2026-05-25
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