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Medik8 C-Tetra® 30ml

Medik8 C-Tetra® 30ml

%0 4.73 | 806 reviews
Box

£42.00 (£1.40 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.

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Rated 4 out of 5 by from Smells divine and leaves a Smells divine and leaves a dewy glow. I am new to vitamin C but the product is gentle enough to not irritate my skin - this is important for me as I am also using retinol. However, unfortunately the serum leaks out of the applicator when taken out of the bottle, resulting in wastage. Aside from that, the product is great!
Date published: 2025-06-11
Rated 5 out of 5 by from I love this oil, my I love this oil, my skin can be dry and this just provides a lovely base,
Date published: 2025-06-09
Rated 5 out of 5 by from I use morning and night. I use morning and night. Super hydrating throughout the day and wake up feeling hydrated too. Skin appears brighter now and less fatigued looking. I will buy again.
Date published: 2025-06-07
Rated 4 out of 5 by from C-tetra Very like this vitamin C. It is very gentle and glides very nicely over the skin. Smells and feel great.
Date published: 2025-06-07
Rated 5 out of 5 by from This really does make my This really does make my skin look brighter and refreshed without an oily feel.
Date published: 2025-06-07
Rated 5 out of 5 by from Love this tetra so much. Love this tetra so much. Soaks into my skin lovely before applying the vitamin c SPF. It took a couple of weeks to get used to it but now my skin loves it and I wouldn’t go without it.
Date published: 2025-06-07
Rated 5 out of 5 by from Low the consistency and glow Low the consistency and glow it gives your skin . I can’t face the morning without it!
Date published: 2025-06-06
Rated 5 out of 5 by from 5/5 — Bright, Glowy Skin in a Bottle Medik8 C-Tetra has become a staple in my morning routine. It’s a beautifully light, fast-absorbing serum that gives my skin an instant glow and long-term brightness. I love that it contains tetrahexyldecyl ascorbate, a stable and gentle form of vitamin C, so I don’t have to worry about oxidation or irritation — even with my sensitive skin. Within the first couple of weeks, I noticed my skin looking fresher and more even, and after consistent use, it’s definitely helped fade some old acne marks and sunspots. It layers really well under moisturiser and SPF without pilling, and it leaves no sticky residue.
Date published: 2025-06-05
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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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