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C-Tetra®

Medik8 C-Tetra® 30ml

%0 4.74 | 1018 reviews
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£36.00 £45.00 20% Off (£1.20 per ml)

Free UK delivery

In stock

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

Product Description

Restore the appearance of skin radiance in just 7 days* with Medik8’s cult favourite C-Tetra serum.

Expertly formulated by their skincare experts with a stabilised form of vitamin C (tetrahexyldecyl ascorbate ), this lightweight serum reduces the appearance of fine lines and wrinkles and visibly brightens uneven skin tone - all while remaining gentle on sensitive skin.

The addition of antioxidant-rich vitamin E protects the skin against the damaging and ageing effects of free radicals for a more healthy, youthful-looking complexion overall. The perfect daily serum for those who are new to vitamin C, or have sensitive skin.
*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin.

Key Benefits:
Increased Skin Youthfulness
Proven to smooth the appearance of fine lines and wrinkles and visibly boost skin's radiance in 7 days*
*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin.

Brighter, More Even Complexion
Proven to visibly brighten the skin in 7 days* and reduce the appearance of wrinkles & dark spots in 4 weeks*
*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin.

Gentle, Lightweight Nourishment
The jojoba seed oil-based formula delivers non-greasy yet effective nourishment for visibly comforted and softer skin.
87% of sensitive skins agree this is the most gentle vitamin C serum they have ever used*
96% of sensitive skins agreed C-Tetra was gentle on the skin*
*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin.

Proven Results:
7 days to restored skin radiance*
7 days to visibly brighter
96% of sensitive skins agreed C-Tetra was gentle on the skin*
4 weeks to visibly reduced wrinkles & dark spots*
90% agree skin feels instantly softer*
*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin.

Key Ingredients:
Stabilised Vitamin C (tetrahexyldecyl ascorbate)
This stable, low-irritation form of vitamin C is incredibly effective on the skin; delivering exceptional protection against ageing free radicals. Supporting collagen production and brightening the skin tone, it leaves the complexion visibly more even, radiant and youthful-looking.

Vitamin E
Rich in antioxidants, vitamin E helps to protect the skin against ageing free radicals. It also helps to boost the power of vitamin C for maximum visible results.

Good to Know:
NO ARTIFICIAL FRAGRANCE
NO SYNTHETIC COLOURS
PARABEN FREE
CERTIFIED BY THE VEGAN SOCIETY

Directions

STEP 1
After cleansing in the morning, massage 4 drops across the face, neck and décolletage.

STEP 2
Leave to absorb before applying sunscreen. We recommend Advanced Day Ultimate Protect.

How to Layer C-Tetra
AM: Apply C-Tetra after cleansing and toning in your morning skincare routine. Always follow with sunscreen.

Ingredients

Simmondsia Chinensis (Jojoba) Seed Oil, Cyclopentasiloxane, Cyclohexasiloxane, Tetrahexyldecyl Ascorbate, Citrus Grandis (Grapefruit) Peel Oil, Tocopheryl Acetate, PPG-12/SMDI Copolymer, Limonene, Citral, Linalool, Geraniol.

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

See more...

Rated 5 out of 5 by from 10/10 [This review was collected as part of a promotion.] Medik8 C-Tetra has quickly become a staple in my skincare routine. The lightweight, silky formula absorbs into my skin without leaving any greasy residue but leaves me with a lovely glow. After a few weeks of consistent application, I noticed a visible improvement in my skin’s brightness - it looked radiant, even-toned, and healthy. I’ve also received several compliments on how fresh and glowing my skin looks. It has been gentle on my skin with no irritation following daily use.
Date published: 2026-05-05
Rated 5 out of 5 by from Glowy skin [This review was collected as part of a promotion.] Lovely texture, layers well, leaves a healthy glow
Date published: 2026-05-04
Rated 4 out of 5 by from Vitamin C It is a great serum but I do prefer the Luxe version
Date published: 2026-05-04
Rated 5 out of 5 by from Love it [This review was collected as part of a promotion.] Love this oil. Very easy to use, I just layer it under the vit C moisturiser every morning, make up goes on lovely over the top. But be warned a little goes a long way!
Date published: 2026-05-03
Rated 5 out of 5 by from Good [This review was collected as part of a promotion.] I was unsure if this strength would be sufficient for my perimenopausal skin but it is adequate. I just feel that the 20% product is far superior because it has exosomes. I won’t downgrade it because Medik8 does explain suitability according to needs.
Date published: 2026-05-03
Rated 5 out of 5 by from Brilliant [This review was collected as part of a promotion.] My favourite vitamin c. Beautifully absorbed into skin. Not greasy at all and great under my favourite moisturiser. You can really see a difference to skin brightness and texture.
Date published: 2026-05-01
Rated 5 out of 5 by from I’ve been using this product [This review was collected as part of a promotion.] I’ve been using this product for a few weeks now and I can already tell a difference in brightness of my skin. I love it
Date published: 2026-04-30
Rated 5 out of 5 by from Light Vitamin C [This review was collected as part of a promotion.] This is a light serum and easily absorbed if less potent than others available.
Date published: 2026-04-28
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Can I use this serum under eyes?

Asked by: Anonymous
Yes absolutely! 
Answered by: Anonymous
Date published: 2023-05-24

What % vitamin c?

Asked by: Anonymous
The tetrahexyldecyl ascorbate (Vitamin C) in C-Tetra serum is 7%.
Answered by: Anonymous
Date published: 2023-05-24

What percentage of vitamin c does this contain?

Asked by: Anonymous
30%
Answered by: Anonymous
Date published: 2023-03-04
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