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C-Tetra®

Medik8 C-Tetra® 30ml

%0 4.74 | 952 reviews
Box

£45.00 (£1.50 per ml)

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.

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Rated 5 out of 5 by from Love [This review was collected as part of a promotion.] Really like the consistency of this. Doesn’t feel greasy at all. Brightening and glowy on the skin
Date published: 2026-03-29
Rated 5 out of 5 by from LOVE THIS! [This review was collected as part of a promotion.] I have sensitive skin and need to be careful with serums but this is such a great product for me. The texture is so soft and such great quality! Perfect consistency before my day-cream.
Date published: 2026-03-28
Rated 5 out of 5 by from Beautiful product [This review was collected as part of a promotion.] Excellent vitamin c product leaves skin looking beautiful
Date published: 2026-03-28
Rated 5 out of 5 by from Amazing product [This review was collected as part of a promotion.] Gives instant results! It evens out skin tone and my skin glows after applying makeup. Wouldn't be without it.
Date published: 2026-03-28
Rated 5 out of 5 by from Game changer [This review was collected as part of a promotion.] Game changer to my skin routine the product I never knew I needed !
Date published: 2026-03-27
Rated 5 out of 5 by from Great Vit C! [This review was collected as part of a promotion.] Lightweight and non-greasy product. Absorbs wonderfully.
Date published: 2026-03-27
Rated 5 out of 5 by from Lightweight + Nourishing [This review was collected as part of a promotion.] So lightweight + nourishing. My skin drinks it in! I’m on me second bottle.
Date published: 2026-03-27
Rated 5 out of 5 by from Excellent [This review was collected as part of a promotion.] My sensitive skin with rosacea loves this form of vitamin C serum.
Date published: 2026-03-27
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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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