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C-Tetra®

Medik8 C-Tetra® 30ml

%0 4.74 | 988 reviews
Box

£45.00 (£1.50 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.

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Rated 5 out of 5 by from Perfect for sensitive skin [This review was collected as part of a promotion.] Very nice serum, hydrating and making skin brighter and nourished. The only thing I need to be careful about is the texture - I am quite clumsy and this serum is very runny, it’s easy to spill on the floor. Beside that - it’s great.
Date published: 2026-04-08
Rated 5 out of 5 by from This Works [This review was collected as part of a promotion.] This was on special offer so I thought I’d try it. Although it is the weakest Vitamin C serum that Medik8 do, I am so impressed with the results. My 75 year old skin is definitely clearer and brighter. I’m going to try the Advanced one next.
Date published: 2026-04-08
Rated 5 out of 5 by from Love it My favourite vitamin C serum. Leaves my skin bright, plump and looking healthy.
Date published: 2026-04-08
Rated 4 out of 5 by from This has the consistency of [This review was collected as part of a promotion.] This has the consistency of a really thin, lightweight oil. I find it a bit hard to spread evenly over the skin without using a lot of product, it does soak in well and doesn’t feel oily or heavy on the skin. I’ve been using for over a month now, every morning. I find I have more of a glow, my dark spots seem less obvious and my fine lines have reduced too. I like it though think I’d probably go up a strength next time.
Date published: 2026-04-08
Rated 5 out of 5 by from Love this product - feels [This review was collected as part of a promotion.] Love this product - feels great on my skin, absorbs easily & works wonders
Date published: 2026-04-07
Rated 5 out of 5 by from I love this product. It [This review was collected as part of a promotion.] I love this product. It goes on so smoothly and smells amazing. I have only just started my skin care regime (I’m a bit late off the mark) but I can see the difference starting already. My skin is feeling softer and is glowing
Date published: 2026-04-07
Rated 5 out of 5 by from I absolutely love this product! [This review was collected as part of a promotion.] I absolutely love this product! The glow I get from it is amazing and I adore the smell! My second time buying and won’t be the last.
Date published: 2026-04-07
Rated 5 out of 5 by from Great results [This review was collected as part of a promotion.] I use on top of my day serum, great results in terms of glow snd comfort
Date published: 2026-04-07
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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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