C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
C-Tetra Advanced
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C-Tetra Advanced
20% Vitamin C Gel-Serum With Phyto Exosomes

Defend against premature skin ageing and achieve accelerated skin brightening with a next-generation combination of 20% vitamin C and skin barrier science. 

Clinically proven to brighten skin and visibly improve wrinkles in 7 days[1] with 0% barrier disruption[1], C-Tetra Advanced is engineered for high-performance visible brightening, skin smoothing, and daily antioxidant defence. 

This intelligent ingredient complex combines potent, stabilised 20% vitamin C with restorative phyto exosomes for enhanced skin resilience and omni-antioxidant acetyl zingerone to neutralise the ageing effects of free radicals.

The result? A high-performance, age-defying vitamin C serum that works smarter, not harsher.
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Key Benefits
Dramatic Skin Brightening

Clinically proven to visibly brighten skin and even tone in 7 days for a radiant, luminous complexion.[1]

Premature Skin Ageing Defence

Shields skin from damaging free radicals, pollution, and daily environmental stressors to help defend against premature skin ageing.

Lightweight Finish

The fast-absorbing gel-serum texture hydrates, smooths, and primes, leaving skin instantly refreshed and ready for the day ahead.

Enhanced Skin Barrier Support

Powerful phyto exosomes deliver replenishing bioactives to skin cells rapidly & effectively, ensuring 0% barrier disruption.[1]

Smooth & Even Complexion

Clinically proven to visibly improve skin smoothness and texture in 7 days, leaving a soft, polished finish.[1]

Proven 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]
90% reduction 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.

[3] Proven via in vitro protein carbonylation study using European standard reference environmental pollutants.
How to Use

First-time use

If you're new to C-Tetra Advanced we recommend a patch test at least 24 hours before first use. Learn how to patch test here.

How To Use

Apply as part of your morning skincare routine. Massage 2-3 pumps across the face, neck and décolletage. Follow with moisturiser and always finish with sunscreen.

Uses Per Tube

80

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.

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.

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.

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.

Full List of Ingredients
C-Tetra Advanced
20% Vitamin C Gel-Serum With Phyto Exosomes

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

*Although we try our best to ensure this list of ingredients is accurate there may be product upgrades from time to time, or slight variants between different regions based on local laws, meaning the only definitive ingredient list is that which is printed on the product packaging.
  • Clinically proven
  • Artificial fragrance free
  • Dermatologically tested
  • Proven gentle formula
  • Certified by the vegan society
  • Non-comedogenic
  • Tested on all skin types & tones
Experts Recommended

C-Tetra Advanced combines the potent power of vitamin C with barrier-supporting phyto exosomes alongside superantioxidant acetyl zingerone, to protect against premature skin aging. C-Tetra Advanced is scientifically proven to shield against the environmental stressors that cause premature skin aging, reducing damage by up to 78%.[3]

Daniel Isaacs
Chief Product Officer & Founding Partner Of Medik8

With this kind of Vitamin C percentage, you're going to get maximum brightness to the skin in just 7 days.

Dr Ewoma Ukeleghe
Medical & Cosmetics Doctor & Medik8 Global Ambassador

It’s rare to see such a powerful brightening treatment that also strengthens and supports skin health from within - this does both.

Dr Bibi Ghalaie
Cosmetic Physician & Medik8 Global Ambassador

The Vitamin C Serum Range

C-Tetra®
Morning
C-Tetra®
(30ml) | €56
Texture
  • Brightening
  • Skin Nourishment
Skin Types

Sensitive Skin

Key Ingredients

Lightweight Oil

Benefits
  • 7% Tetrahexyldecyl Ascorbate
  • Vitamin E
C-Tetra® Luxe
Morning
C-Tetra® Luxe
(30ml) | €82
Texture
  • Brightening
  • Youth Boosting
  • Skin Nourishment
  • Dark Spot Reduction
Skin Types

Dry Skin

Key Ingredients

Rich Oil

Benefits
  • 14% Tetrahexyldecyl Ascorbate
  • Squalane
  • Maracuja Oil
C-Tetra Advanced
Morning
C-Tetra Advanced
| €85
Texture
  • Brightening 
  • Age Defense
  • Skin Nourishment
  • Dark Spot Reduction
  • Smooth & Even Complexion
Skin Types

All skin types, especially oily & combination

Key Ingredients

Lightweight Gel-Serum

Benefits
  • 20% Tetrahexyldecyl Ascorbate
  • Phyto Exosomes 
  • Acetyl Zingerone

Complete Your Regime

Reviews

Frequently Asked Questions

What strength vitamin C is C-Tetra Advanced?
C-Tetra Advanced contains 20% stabilised vitamin C (tetrahexyldecyl ascorbate).
Can I use C-Tetra alongside vitamin A?
Absolutely. In fact we recommend it as part of our pioneering CSA Philosophy which champions vitamin C plus sunscreen by day, vitamin A by night as the simple secret to glowing, youthful-looking skin.
Can I use C-Tetra if I'm pregnant or breastfeeding?
As a cosmetics company, we are unable to provide product advice in relation to medical conditions such as pregnancy. We would recommend discussing the ingredients with your GP or midwife before use. As general guidance, this product does not contain any ingredients which we would recommend to avoid during pregnancy, unless advised by your doctor.
Can I layer C-Tetra Advanced with Liquid Peptides Advanced MP in the morning?
Yes, you can. As C-Tetra Advanced and Liquid Peptides Advanced MP are both emulsion-based serums you can layer one on top of the other interchangeably. When layering multiple serums, we recommend applying in order of thinnest to thickest consistency.
Does C-Tetra Advanced contain fragrance/essential oils?
C-Tetra Advanced is free from artificial fragrances but does contain a natural, uplifting citrus fragrance derived from essential oils. The scent is refreshing and is designed to enhance your experience and offer an energising start to your morning skincare routine. If you are familiar with our C-Tetra and C-Tetra Luxe serums, you can expect to smell the same scent.
Where do I layer C-Tetra Advanced in my routine?
C-Tetra Advanced should be applied in the morning, after cleansing and toning, but before moisturiser and sunscreen. If you are using multiple serums, we recommend applying them in order of thinnest to thickest in texture. Since C-Tetra Advanced is an emulsion, it should be layered on top of water and oil-based serums. This ensures your skin gets the full benefits of each product.
Can I use C-Tetra Advanced if I’ve never used vitamin C before?
Absolutely. Although C-Tetra Advanced contains a potent 20% vitamin C, it has been formulated using a very gentle form of vitamin C called THDA (Tetrahexyldecyl Ascorbate) that is suitable for all skin types, even if you’re new to vitamin C. Alongside this, it contains many gentle actives such as phyto exosomes, which offer soothing properties to support the skin barrier. C-Tetra Advanced is also proven to be gentle on all skin types in independent clinical and consumer testing. This means anyone can enjoy C-Tetra Advanced without fear of irritation.
I think there’s product left in my bottle that I can’t access with the pump. What do I do?
As C-Tetra Advanced is a lightweight emulsion, it is a little thicker than water-based serums and therefore may flow more slowly, however, it was designed for use with a pump so it should still dispense with ease. If there is any residue that the pump is not dispensing, you can unscrew the pump and turn the bottle upside down to pour out any remaining product. This should not be required unless you have used up nearly all of the product.
Where do I layer C-Tetra Advanced in my routine?
C-Tetra Advanced should be applied in the morning, after cleansing and toning, but before moisturiser and sunscreen. If you are using multiple serums, we recommend applying them in order of thinnest to thickest in texture. Since C-Tetra Advanced is an emulsion, it should be layered on top of water and oil-based serums. This ensures your skin gets the full benefits of each product.
Can I use C-Tetra Advanced if I’ve never used vitamin C before?
Absolutely. Although C-Tetra Advanced contains a potent 20% vitamin C, it has been formulated using a very gentle form of vitamin C called THDA (Tetrahexyldecyl Ascorbate) that is suitable for all skin types, even if you’re new to vitamin C. Alongside this, it contains many gentle actives such as phyto exosomes, which offer soothing properties to support the skin barrier. C-Tetra Advanced is also proven to be gentle on all skin types in independent clinical and consumer testing. This means anyone can enjoy C-Tetra Advanced without fear of irritation.
I think there’s product left in my bottle that I can’t access with the pump. What do I do?
As C-Tetra Advanced is a lightweight emulsion, it is a little thicker than water-based serums and therefore may flow more slowly, however, it was designed for use with a pump so it should still dispense with ease. If there is any residue that the pump is not dispensing, you can unscrew the pump and turn the bottle upside down to pour out any remaining product. This should not be required unless you have used up nearly all of the product.
C-Tetra Advanced